Check if removing a given edge disconnects a graph

Here given code implementation process.

Example disconnecting graph by edges
import java.util.ArrayList;
/*
    Java Program
    Check if removing a given edge disconnects a graph
*/
public class Graph
{
    // Number of vertices in graph
    public int vertices;
    // Use to collect edges information
    public ArrayList < ArrayList < Integer >> adjacencylist;
    public Graph(int vertices)
    {
        this.vertices = vertices;
        this.adjacencylist = new ArrayList < ArrayList < Integer >> (vertices);
        for (int i = 0; i < this.vertices; ++i)
        {
            this.adjacencylist.add(new ArrayList < Integer > ());
        }
    }
    public void addEdge(int u, int v)
    {
        if (u < 0 || u >= this.vertices || v < 0 || v >= this.vertices)
        {
            return;
        }
        // Add node edge
        adjacencylist.get(u).add(v);
        adjacencylist.get(v).add(u);
    }
    // Display graph nodes and edges
    public void printGraph()
    {
        System.out.print("\n Graph Adjacency List ");
        for (int i = 0; i < this.vertices; ++i)
        {
            System.out.print(" \n [" + i + "] :");
            // iterate edges of i node
            for (int j = 0; j < this.adjacencylist.get(i).size(); j++)
            {
                System.out.print("  " + this.adjacencylist.get(i).get(j));
            }
        }
    }
    public void dfs(boolean[] visited, int start)
    {
        if (start < 0 || start >= this.vertices)
        {
            // In case given invalid node
            return;
        }
        // Mark a current visited node
        visited[start] = true;

        int i = 0;
        // Execute edges of given start vertices
        while (i < adjacencylist.get(start).size())
        {
            if (visited[adjacencylist.get(start).get(i)] == false)
            {
                // When edge node not visiting, then perform DFS operation
                dfs(visited, adjacencylist.get(start).get(i));
            }
            // Visit to next node
            i++;
        }
    }

    public int edgePosition(int u, int v)
    {

        int i = 0;
        while(i < this.adjacencylist.get(u).size())
        {
            if(this.adjacencylist.get(u).get(i)==v)
            {
                return i;
            }
            i++;
        }
        return -1;
    }   

    public boolean removeNodeEdge(int u, int v)
    {

        if(u < 0 || v < 0 || u > this.vertices 
            || v > this.vertices )
        {
            return false;
        }
        int a = edgePosition(u,v);
        int b = edgePosition(v,u);

        if(a==-1 || b == -1)
        {
            // Given edge are not exist between given nodes 
            return false;
        }
        // Remove edges
        this.adjacencylist.get(u).remove(a);
        this.adjacencylist.get(v).remove(b);

        return true;

    }
    public void unsetVisit(boolean[] visited)
    {
        for (int i = 0; i < this.vertices; ++i)
        {
            visited[i] = false;
        }
    }
    public boolean isAllVerticesVisit(boolean[] visited)
    {
        for (int i = 0; i < this.vertices; ++i)
        {
            if(visited[i]==false)
            {
                return false;
            }
        }
        return true;
    }
    public void disconnectByEdge(int u, int v)
    {


        boolean[] visited = new boolean[this.vertices];
     
        unsetVisit(visited);

        dfs(visited, 0);

   

        if(isAllVerticesVisit(visited)==true)
        {

            if(removeNodeEdge(u,v)==true)
            {
               
                unsetVisit(visited);

                dfs(visited, 0);

                // Add remove edge
                addEdge(u,v); 

                if(isAllVerticesVisit(visited))
                {
                    // not a bridge edge
                    // graph are not disconnect
          
                    System.out.print("\n Remove edge ["+u+"-"+v+"] not disconnecting this graph ");
                }
                else
                {
             
                    System.out.print("\n Remove edge ["+u+"-"+v+"] disconnecting this graph ");
                }
               
            }
            else
            {
                // When edges are not exist
                System.out.print("\n No edge between vertices ["+u+"-"+v+"]");
            }
        }
        else
        {
            // When graph is already disconnected?
              System.out.print("\n Graph is already disconnected");
        }
     
    }
    public static void main(String[] args)
    {
        Graph graph = new Graph(12);
        graph.addEdge(0, 1);
        graph.addEdge(0, 3);
        graph.addEdge(0, 4);
        graph.addEdge(1, 2);
        graph.addEdge(1, 5);
        graph.addEdge(2, 3);
        graph.addEdge(2, 6);
        graph.addEdge(3, 4);
        graph.addEdge(3, 9);
        graph.addEdge(6, 7);
        graph.addEdge(6, 8);
        graph.addEdge(9, 10);
        graph.addEdge(9, 11);
        graph.addEdge(10, 11);
        // Display graph element
        graph.printGraph();

        // Test case
        graph.disconnectByEdge(4,7);
        graph.disconnectByEdge(3,9);
        graph.disconnectByEdge(1,2);
        graph.disconnectByEdge(6,2);
        graph.disconnectByEdge(10,11);

    }
}

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph
// Include header file
#include <iostream>
#include <vector>

using namespace std;
/*
    C++ Program
    Check if removing a given edge disconnects a graph
*/
class Graph
{
	public:
	// Number of vertices in graph
	int vertices;
	// Use to collect edges information
	vector < vector < int > > adjacencylist;
	Graph(int vertices)
	{
		this->vertices = vertices;
		for (int i = 0; i < this->vertices; ++i)
		{
			this->adjacencylist.push_back( vector < int > ());
		}
	}
	void addEdge(int u, int v)
	{
		if (u < 0 || u >= this->vertices || v < 0 || v >= this->vertices)
		{
			return;
		}
		// Add node edge
		this->adjacencylist.at(u).push_back(v);
		this->adjacencylist.at(v).push_back(u);
	}
	// Display graph nodes and edges
	void printGraph()
	{
		cout << "\n Graph Adjacency List ";
		for (int i = 0; i < this->vertices; ++i)
		{
			cout << " \n [" << i << "] :";
			// iterate edges of i node
			for (int j = 0; j < this->adjacencylist.at(i).size(); j++)
			{
				cout << "  " << this->adjacencylist.at(i).at(j);
			}
		}
	}
	void dfs(bool visited[], int start)
	{
		if (start < 0 || start >= this->vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		visited[start] = true;
		int i = 0;
		// Execute edges of given start vertices
		while (i < this->adjacencylist.at(start).size())
		{
			if (visited[this->adjacencylist.at(start).at(i)] == false)
			{
				// When edge node not visiting, then perform DFS operation
				this->dfs(visited, this->adjacencylist.at(start).at(i));
			}
			// Visit to next node
			i++;
		}
	}
	int edgePosition(int u, int v)
	{
		int i = 0;
		while (i < this->adjacencylist.at(u).size())
		{
			if (this->adjacencylist.at(u).at(i) == v)
			{
				return i;
			}
			i++;
		}
		return -1;
	}
	bool removeNodeEdge(int u, int v)
	{
		if (u < 0 || v < 0 || u > this->vertices || v > this->vertices)
		{
			return false;
		}
		int a = this->edgePosition(u, v);
		int b = this->edgePosition(v, u);
		if (a == -1 || b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		this->adjacencylist.at(u).erase(this->adjacencylist.at(u).begin() + a);
		this->adjacencylist.at(v).erase(this->adjacencylist.at(v).begin() + b);
		return true;
	}
	void unsetVisit(bool visited[])
	{
		for (int i = 0; i < this->vertices; ++i)
		{
			visited[i] = false;
		}
	}
	bool isAllVerticesVisit(bool visited[])
	{
		for (int i = 0; i < this->vertices; ++i)
		{
			if (visited[i] == false)
			{
				return false;
			}
		}
		return true;
	}
	void disconnectByEdge(int u, int v)
	{
		bool visited[this->vertices];
		this->unsetVisit(visited);
		this->dfs(visited, 0);
		if (this->isAllVerticesVisit(visited) == true)
		{
			if (this->removeNodeEdge(u, v) == true)
			{
				this->unsetVisit(visited);
				this->dfs(visited, 0);
				// Add remove edge
				this->addEdge(u, v);
				if (this->isAllVerticesVisit(visited))
				{
					// not a bridge edge
					// graph are not disconnect
					cout << "\n Remove edge [" << u << "-" 
                  		 << v << "] not disconnecting this graph ";
				}
				else
				{
					cout << "\n Remove edge [" << u << "-" 
                  		 << v << "] disconnecting this graph ";
				}
			}
			else
			{
				// When edges are not exist
				cout << "\n No edge between vertices [" << u << "-" 
              											<< v << "]";
			}
		}
		else
		{
			// When graph is already disconnected?
			cout << "\n Graph is already disconnected";
		}
	}
};
int main()
{
	Graph *graph = new Graph(12);
	graph->addEdge(0, 1);
	graph->addEdge(0, 3);
	graph->addEdge(0, 4);
	graph->addEdge(1, 2);
	graph->addEdge(1, 5);
	graph->addEdge(2, 3);
	graph->addEdge(2, 6);
	graph->addEdge(3, 4);
	graph->addEdge(3, 9);
	graph->addEdge(6, 7);
	graph->addEdge(6, 8);
	graph->addEdge(9, 10);
	graph->addEdge(9, 11);
	graph->addEdge(10, 11);
	// Display graph element
	graph->printGraph();
	// Test case
	graph->disconnectByEdge(4, 7);
	graph->disconnectByEdge(3, 9);
	graph->disconnectByEdge(1, 2);
	graph->disconnectByEdge(6, 2);
	graph->disconnectByEdge(10, 11);
	return 0;
}

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph
// Include namespace system
using System;
using System.Collections.Generic;
/*
    Csharp Program
    Check if removing a given edge disconnects a graph
*/
public class Graph
{
	// Number of vertices in graph
	public int vertices;
	// Use to collect edges information
	public List < List < int >> adjacencylist;
	public Graph(int vertices)
	{
		this.vertices = vertices;
		this.adjacencylist = new List < List < int >> (vertices);
		for (int i = 0; i < this.vertices; ++i)
		{
			this.adjacencylist.Add(new List < int > ());
		}
	}
	public void addEdge(int u, int v)
	{
		if (u < 0 || u >= this.vertices || v < 0 || v >= this.vertices)
		{
			return;
		}
		// Add node edge
		this.adjacencylist[u].Add(v);
		this.adjacencylist[v].Add(u);
	}
	// Display graph nodes and edges
	public void printGraph()
	{
		Console.Write("\n Graph Adjacency List ");
		for (int i = 0; i < this.vertices; ++i)
		{
			Console.Write(" \n [" + i + "] :");
			// iterate edges of i node
			for (int j = 0; j < this.adjacencylist[i].Count; j++)
			{
				Console.Write("  " + this.adjacencylist[i][j]);
			}
		}
	}
	public void dfs(Boolean[] visited, int start)
	{
		if (start < 0 || start >= this.vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		visited[start] = true;
		int i = 0;
		// Execute edges of given start vertices
		while (i < this.adjacencylist[start].Count)
		{
			if (visited[this.adjacencylist[start][i]] == false)
			{
				// When edge node not visiting, then perform DFS operation
				this.dfs(visited, this.adjacencylist[start][i]);
			}
			// Visit to next node
			i++;
		}
	}
	public int edgePosition(int u, int v)
	{
		int i = 0;
		while (i < this.adjacencylist[u].Count)
		{
			if (this.adjacencylist[u][i] == v)
			{
				return i;
			}
			i++;
		}
		return -1;
	}
	public Boolean removeNodeEdge(int u, int v)
	{
		if (u < 0 || v < 0 || u > this.vertices || v > this.vertices)
		{
			return false;
		}
		int a = this.edgePosition(u, v);
		int b = this.edgePosition(v, u);
		if (a == -1 || b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		this.adjacencylist[u].RemoveAt(a);
		this.adjacencylist[v].RemoveAt(b);
		return true;
	}
	public void unsetVisit(Boolean[] visited)
	{
		for (int i = 0; i < this.vertices; ++i)
		{
			visited[i] = false;
		}
	}
	public Boolean isAllVerticesVisit(Boolean[] visited)
	{
		for (int i = 0; i < this.vertices; ++i)
		{
			if (visited[i] == false)
			{
				return false;
			}
		}
		return true;
	}
	public void disconnectByEdge(int u, int v)
	{
		Boolean[] visited = new Boolean[this.vertices];
		this.unsetVisit(visited);
		this.dfs(visited, 0);
		if (this.isAllVerticesVisit(visited) == true)
		{
			if (this.removeNodeEdge(u, v) == true)
			{
				this.unsetVisit(visited);
				this.dfs(visited, 0);
				// Add remove edge
				this.addEdge(u, v);
				if (this.isAllVerticesVisit(visited))
				{
					// not a bridge edge
					// graph are not disconnect
					Console.Write("\n Remove edge [" + u + "-" + 
                                  v + "] not disconnecting this graph ");
				}
				else
				{
					Console.Write("\n Remove edge [" + u + "-" + 
                                  v + "] disconnecting this graph ");
				}
			}
			else
			{
				// When edges are not exist
				Console.Write("\n No edge between vertices [" + u + 
                              "-" + v + "]");
			}
		}
		else
		{
			// When graph is already disconnected?
			Console.Write("\n Graph is already disconnected");
		}
	}
	public static void Main(String[] args)
	{
		Graph graph = new Graph(12);
		graph.addEdge(0, 1);
		graph.addEdge(0, 3);
		graph.addEdge(0, 4);
		graph.addEdge(1, 2);
		graph.addEdge(1, 5);
		graph.addEdge(2, 3);
		graph.addEdge(2, 6);
		graph.addEdge(3, 4);
		graph.addEdge(3, 9);
		graph.addEdge(6, 7);
		graph.addEdge(6, 8);
		graph.addEdge(9, 10);
		graph.addEdge(9, 11);
		graph.addEdge(10, 11);
		// Display graph element
		graph.printGraph();
		// Test case
		graph.disconnectByEdge(4, 7);
		graph.disconnectByEdge(3, 9);
		graph.disconnectByEdge(1, 2);
		graph.disconnectByEdge(6, 2);
		graph.disconnectByEdge(10, 11);
	}
}

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph
package main
import "fmt"
/*
    Go Program
    Check if removing a given edge disconnects a graph
*/
type Graph struct {
	// Number of vertices in graph
	vertices int
	// Use to collect edges information
	adjacencylist [][]int
}
func getGraph(vertices int) * Graph {
	var me *Graph = &Graph {}
	me.vertices = vertices
	me.adjacencylist = make([][]int,vertices)

	return me
}
func(this Graph) addEdge(u, v int) {
	if u < 0 || u >= this.vertices || v < 0 || v >= this.vertices {
		return
	}
	// Add node edge
	this.adjacencylist[u] = append(this.adjacencylist[u], v)
	this.adjacencylist[v] = append(this.adjacencylist[v], u)
}
// Display graph nodes and edges
func(this Graph) printGraph() {
	fmt.Print("\n Graph Adjacency List ")
	for i := 0 ; i < this.vertices ; i++ {
		fmt.Print(" \n [", i, "] :")
		// iterate edges of i node
		for j := 0 ; j < len(this.adjacencylist[i]) ; j++ {
			fmt.Print("  ", this.adjacencylist[i][j])
		}
	}
}
func(this Graph) dfs(visited[] bool, start int) {
	if start < 0 || start >= this.vertices {
		// In case given invalid node
		return
	}
	// Mark a current visited node
	visited[start] = true
	var i int = 0
	// Execute edges of given start vertices
	for (i < len(this.adjacencylist[start])) {
		if visited[this.adjacencylist[start][i]] == false {
			// When edge node not visiting, then perform DFS operation
			this.dfs(visited, this.adjacencylist[start][i])
		}
		// Visit to next node
		i++
	}
}
func(this Graph) edgePosition(u, v int) int {
	var i int = 0
	for (i < len(this.adjacencylist[u])) {
		if this.adjacencylist[u][i] == v {
			return i
		}
		i++
	}
	return -1
}
func(this Graph) removeNodeEdge(u, v int) bool {
	if u < 0 || v < 0 || u > this.vertices || v > this.vertices {
		return false
	}
	var a int = this.edgePosition(u, v)
	var b int = this.edgePosition(v, u)
	if a == -1 || b == -1 {
		// Given edge are not exist between given nodes 
		return false
	}
	// Remove edges
	this.adjacencylist[u] = append(this.adjacencylist[u][:a], 
		this.adjacencylist[u][(a+1):]...)
	this.adjacencylist[v] = append(this.adjacencylist[v][:b], 
		this.adjacencylist[v][(b+1):]...)

	return true
}
func(this Graph) unsetVisit(visited[] bool) {
	for i := 0 ; i < this.vertices ; i++ {
		visited[i] = false
	}
}
func(this Graph) isAllVerticesVisit(visited[] bool) bool {
	for i := 0 ; i < this.vertices ; i++ {
		if visited[i] == false {
			return false
		}
	}
	return true
}
func(this Graph) disconnectByEdge(u, v int) {
	var visited = make([]bool,this.vertices)
	this.unsetVisit(visited)
	this.dfs(visited, 0)
	if this.isAllVerticesVisit(visited) == true {
		if this.removeNodeEdge(u, v) == true {
			this.unsetVisit(visited)
			this.dfs(visited, 0)
			// Add remove edge
			this.addEdge(u, v)
			if this.isAllVerticesVisit(visited) {
				// not a bridge edge
				// graph are not disconnect
				fmt.Print("\n Remove edge [", u, "-", v, "] not disconnecting this graph ")
			} else {
				fmt.Print("\n Remove edge [", u, "-", v, "] disconnecting this graph ")
			}
		} else {
			// When edges are not exist
			fmt.Print("\n No edge between vertices [", u, "-", v, "]")
		}
	} else {
		// When graph is already disconnected?
		fmt.Print("\n Graph is already disconnected")
	}
}
func main() {
	var graph * Graph = getGraph(12)
	graph.addEdge(0, 1)
	graph.addEdge(0, 3)
	graph.addEdge(0, 4)
	graph.addEdge(1, 2)
	graph.addEdge(1, 5)
	graph.addEdge(2, 3)
	graph.addEdge(2, 6)
	graph.addEdge(3, 4)
	graph.addEdge(3, 9)
	graph.addEdge(6, 7)
	graph.addEdge(6, 8)
	graph.addEdge(9, 10)
	graph.addEdge(9, 11)
	graph.addEdge(10, 11)
	// Display graph element
	graph.printGraph()
	// Test case
	graph.disconnectByEdge(4, 7)
	graph.disconnectByEdge(3, 9)
	graph.disconnectByEdge(1, 2)
	graph.disconnectByEdge(6, 2)
	graph.disconnectByEdge(10, 11)
}

input

 Graph Adjacency List  
 [0] :  1  3  4 
 [1] :  0  2  5 
 [2] :  1  3  6 
 [3] :  0  2  4  9 
 [4] :  0  3 
 [5] :  1 
 [6] :  2  7  8 
 [7] :  6 
 [8] :  6 
 [9] :  3  10  11 
 [10] :  9  11 
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph 
 Remove edge [1-2] not disconnecting this graph 
 Remove edge [6-2] disconnecting this graph 
 Remove edge [10-11] not disconnecting this graph
<?php
/*
    Php Program
    Check if removing a given edge disconnects a graph
*/
class Graph
{
	// Number of vertices in graph
	public $vertices;
	// Use to collect edges information
	public $adjacencylist;
	public	function __construct($vertices)
	{
		$this->vertices = $vertices;
		$this->adjacencylist = array();
		for ($i = 0; $i < $this->vertices; ++$i)
		{
			$this->adjacencylist[] = array();
		}
	}
	public	function addEdge($u, $v)
	{
		if ($u < 0 || $u >= $this->vertices || 
            $v < 0 || $v >= $this->vertices)
		{
			return;
		}
		// Add node edge
		$this->adjacencylist[$u][] = $v;
		$this->adjacencylist[$v][] = $u;
	}
	// Display graph nodes and edges
	public	function printGraph()
	{
		echo("\n Graph Adjacency List ");
		for ($i = 0; $i < $this->vertices; ++$i)
		{
			echo(" \n [".$i.
				"] :");
			// iterate edges of i node
			for ($j = 0; $j < count($this->adjacencylist[$i]); $j++)
			{
				echo("  ".$this->adjacencylist[$i][$j]);
			}
		}
	}
	public	function dfs(&$visited, $start)
	{
		if ($start < 0 || $start >= $this->vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		$visited[$start] = true;
		$i = 0;
		// Execute edges of given start vertices
		while ($i < count($this->adjacencylist[$start]))
		{
			if ($visited[$this->adjacencylist[$start][$i]] == false)
			{
				// When edge node not visiting, then perform DFS operation
				$this->dfs($visited, $this->adjacencylist[$start][$i]);
			}
			// Visit to next node
			$i++;
		}
	}
	public	function edgePosition($u, $v)
	{
		$i = 0;
		while ($i < count($this->adjacencylist[$u]))
		{
			if ($this->adjacencylist[$u][$i] == $v)
			{
				return $i;
			}
			$i++;
		}
		return -1;
	}
	public	function removeNodeEdge($u, $v)
	{
		if ($u < 0 || $v < 0 || 
            $u > $this->vertices || $v > $this->vertices)
		{
			return false;
		}
		$a = $this->edgePosition($u, $v);
		$b = $this->edgePosition($v, $u);
		if ($a == -1 || $b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		array_splice($this->adjacencylist[$u],$a,1);
		array_splice($this->adjacencylist[$v],$b,1);
		return true;
	}
	public	function unsetVisit(&$visited)
	{
		for ($i = 0; $i < $this->vertices; ++$i)
		{
			$visited[$i] = false;
		}
	}
	public	function isAllVerticesVisit($visited)
	{
		for ($i = 0; $i < $this->vertices; ++$i)
		{
			if ($visited[$i] == false)
			{
				return false;
			}
		}
		return true;
	}
	public	function disconnectByEdge($u, $v)
	{
		$visited = array_fill(0, $this->vertices, false);
		$this->unsetVisit($visited);
		$this->dfs($visited, 0);
		if ($this->isAllVerticesVisit($visited) == true)
		{
			if ($this->removeNodeEdge($u, $v) == true)
			{
				$this->unsetVisit($visited);
				$this->dfs($visited, 0);
				// Add remove edge
				$this->addEdge($u, $v);
				if ($this->isAllVerticesVisit($visited))
				{
					// not a bridge edge
					// graph are not disconnect
					echo("\n Remove edge [".$u.
						"-".$v.
						"] not disconnecting this graph ");
				}
				else
				{
					echo("\n Remove edge [".$u.
						"-".$v.
						"] disconnecting this graph ");
				}
			}
			else
			{
				// When edges are not exist
				echo("\n No edge between vertices [".$u.
					"-".$v.
					"]");
			}
		}
		else
		{
			// When graph is already disconnected?
			echo("\n Graph is already disconnected");
		}
	}
}

function main()
{
	$graph = new Graph(12);
	$graph->addEdge(0, 1);
	$graph->addEdge(0, 3);
	$graph->addEdge(0, 4);
	$graph->addEdge(1, 2);
	$graph->addEdge(1, 5);
	$graph->addEdge(2, 3);
	$graph->addEdge(2, 6);
	$graph->addEdge(3, 4);
	$graph->addEdge(3, 9);
	$graph->addEdge(6, 7);
	$graph->addEdge(6, 8);
	$graph->addEdge(9, 10);
	$graph->addEdge(9, 11);
	$graph->addEdge(10, 11);
	// Display graph element
	$graph->printGraph();
	// Test case
	$graph->disconnectByEdge(4, 7);
	$graph->disconnectByEdge(3, 9);
	$graph->disconnectByEdge(1, 2);
	$graph->disconnectByEdge(6, 2);
	$graph->disconnectByEdge(10, 11);
}
main();

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph
/*
    Node JS Program
    Check if removing a given edge disconnects a graph
*/
class Graph
{
	constructor(vertices)
	{
		this.vertices = vertices;
		this.adjacencylist = [];
		for (var i = 0; i < this.vertices; ++i)
		{
			this.adjacencylist.push([]);
		}
	}
	addEdge(u, v)
	{
		if (u < 0 || u >= this.vertices || 
            v < 0 || v >= this.vertices)
		{
			return;
		}
		// Add node edge
		this.adjacencylist[u].push(v);
		this.adjacencylist[v].push(u);
	}
	// Display graph nodes and edges
	printGraph()
	{
		process.stdout.write("\n Graph Adjacency List ");
		for (var i = 0; i < this.vertices; ++i)
		{
			process.stdout.write(" \n [" + i + "] :");
			// iterate edges of i node
			for (var j = 0; j < this.adjacencylist[i].length; j++)
			{
				process.stdout.write("  " + this.adjacencylist[i][j]);
			}
		}
	}
	dfs(visited, start)
	{
		if (start < 0 || start >= this.vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		visited[start] = true;
		var i = 0;
		// Execute edges of given start vertices
		while (i < this.adjacencylist[start].length)
		{
			if (visited[this.adjacencylist[start][i]] == false)
			{
				// When edge node not visiting, then perform DFS operation
				this.dfs(visited, this.adjacencylist[start][i]);
			}
			// Visit to next node
			i++;
		}
	}
	edgePosition(u, v)
	{
		var i = 0;
		while (i < this.adjacencylist[u].length)
		{
			if (this.adjacencylist[u][i] == v)
			{
				return i;
			}
			i++;
		}
		return -1;
	}
	removeNodeEdge(u, v)
	{
		if (u < 0 || v < 0 || 
            u > this.vertices || v > this.vertices)
		{
			return false;
		}
		var a = this.edgePosition(u, v);
		var b = this.edgePosition(v, u);
		if (a == -1 || b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		this.adjacencylist[u].splice(a, 1);
		this.adjacencylist[v].splice(b, 1);
		return true;
	}
	unsetVisit(visited)
	{
		for (var i = 0; i < this.vertices; ++i)
		{
			visited[i] = false;
		}
	}
	isAllVerticesVisit(visited)
	{
		for (var i = 0; i < this.vertices; ++i)
		{
			if (visited[i] == false)
			{
				return false;
			}
		}
		return true;
	}
	disconnectByEdge(u, v)
	{
		var visited = Array(this.vertices).fill(false);
		this.unsetVisit(visited);
		this.dfs(visited, 0);
		if (this.isAllVerticesVisit(visited) == true)
		{
			if (this.removeNodeEdge(u, v) == true)
			{
				this.unsetVisit(visited);
				this.dfs(visited, 0);
				// Add remove edge
				this.addEdge(u, v);
				if (this.isAllVerticesVisit(visited))
				{
					// not a bridge edge
					// graph are not disconnect
					process.stdout.write("\n Remove edge [" + 
                      u + "-" + v + "] not disconnecting this graph ");
				}
				else
				{
					process.stdout.write("\n Remove edge [" + 
                      u + "-" + v + "] disconnecting this graph ");
				}
			}
			else
			{
				// When edges are not exist
				process.stdout.write("\n No edge between vertices [" + 
                                    u + "-" + v + "]");
			}
		}
		else
		{
			// When graph is already disconnected?
			process.stdout.write("\n Graph is already disconnected");
		}
	}
}

function main()
{
	var graph = new Graph(12);
	graph.addEdge(0, 1);
	graph.addEdge(0, 3);
	graph.addEdge(0, 4);
	graph.addEdge(1, 2);
	graph.addEdge(1, 5);
	graph.addEdge(2, 3);
	graph.addEdge(2, 6);
	graph.addEdge(3, 4);
	graph.addEdge(3, 9);
	graph.addEdge(6, 7);
	graph.addEdge(6, 8);
	graph.addEdge(9, 10);
	graph.addEdge(9, 11);
	graph.addEdge(10, 11);
	// Display graph element
	graph.printGraph();
	// Test case
	graph.disconnectByEdge(4, 7);
	graph.disconnectByEdge(3, 9);
	graph.disconnectByEdge(1, 2);
	graph.disconnectByEdge(6, 2);
	graph.disconnectByEdge(10, 11);
}
main();

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph
#    Python 3 Program
#    Check if removing a given edge disconnects a graph
class Graph :
	#  Number of vertices in graph
	#  Use to collect edges information
	def __init__(self, vertices) :
		self.vertices = vertices
		self.adjacencylist = []
		i = 0
		while (i < self.vertices) :
			self.adjacencylist.append([])
			i += 1
		
	
	def addEdge(self, u, v) :
		if (u < 0 or u >= self.vertices or 
            v < 0 or v >= self.vertices) :
			return
		
		#  Add node edge
		self.adjacencylist[u].append(v)
		self.adjacencylist[v].append(u)
	
	#  Display graph nodes and edges
	def printGraph(self) :
		print("\n Graph Adjacency List ", end = "")
		i = 0
		while (i < self.vertices) :
			print(" \n [", i ,"] :", end = "")
			j = 0
			#  iterate edges of i node
			while (j < len(self.adjacencylist[i])) :
				print("  ", self.adjacencylist[i][j], end = "")
				j += 1
			
			i += 1
		
	
	def dfs(self, visited, start) :
		if (start < 0 or start >= self.vertices) :
			#  In case given invalid node
			return
		
		#  Mark a current visited node
		visited[start] = True
		i = 0
		#  Execute edges of given start vertices
		while (i < len(self.adjacencylist[start])) :
			if (visited[self.adjacencylist[start][i]] == False) :
				#  When edge node not visiting, then perform DFS operation
				self.dfs(visited, self.adjacencylist[start][i])
			
			#  Visit to next node
			i += 1
		
	
	def edgePosition(self, u, v) :
		i = 0
		while (i < len(self.adjacencylist[u])) :
			if (self.adjacencylist[u][i] == v) :
				return i
			
			i += 1
		
		return -1
	
	def removeNodeEdge(self, u, v) :
		if (u < 0 or v < 0 or u > self.vertices or v > self.vertices) :
			return False
		
		a = self.edgePosition(u, v)
		b = self.edgePosition(v, u)
		if (a == -1 or b == -1) :
			#  Given edge are not exist between given nodes 
			return False
		
		#  Remove edges
		del self.adjacencylist[u][a]
		del self.adjacencylist[v][b]
		return True
	
	def unsetVisit(self, visited) :
		i = 0
		while (i < self.vertices) :
			visited[i] = False
			i += 1
		
	
	def isAllVerticesVisit(self, visited) :
		i = 0
		while (i < self.vertices) :
			if (visited[i] == False) :
				return False
			
			i += 1
		
		return True
	
	def disconnectByEdge(self, u, v) :
		visited = [False] * (self.vertices)
		self.unsetVisit(visited)
		self.dfs(visited, 0)
		if (self.isAllVerticesVisit(visited) == True) :
			if (self.removeNodeEdge(u, v) == True) :
				self.unsetVisit(visited)
				self.dfs(visited, 0)
				#  Add remove edge
				self.addEdge(u, v)
				if (self.isAllVerticesVisit(visited)) :
					#  not a bridge edge
					#  graph are not disconnect
					print("\n Remove edge [", u ,
                          "-", v ,"] not disconnecting this graph ", end = "")
				else :
					print("\n Remove edge [", 
                          u ,"-", v ,"] disconnecting this graph ", end = "")
				
			else :
				#  When edges are not exist
				print("\n No edge between vertices [", 
                      u ,"-", v ,"]", end = "")
			
		else :
			#  When graph is already disconnected?
			print("\n Graph is already disconnected", end = "")
		
	

def main() :
	graph = Graph(12)
	graph.addEdge(0, 1)
	graph.addEdge(0, 3)
	graph.addEdge(0, 4)
	graph.addEdge(1, 2)
	graph.addEdge(1, 5)
	graph.addEdge(2, 3)
	graph.addEdge(2, 6)
	graph.addEdge(3, 4)
	graph.addEdge(3, 9)
	graph.addEdge(6, 7)
	graph.addEdge(6, 8)
	graph.addEdge(9, 10)
	graph.addEdge(9, 11)
	graph.addEdge(10, 11)
	#  Display graph element
	graph.printGraph()
	#  Test case
	graph.disconnectByEdge(4, 7)
	graph.disconnectByEdge(3, 9)
	graph.disconnectByEdge(1, 2)
	graph.disconnectByEdge(6, 2)
	graph.disconnectByEdge(10, 11)

if __name__ == "__main__": main()

input

 Graph Adjacency List
 [ 0 ] :   1   3   4
 [ 1 ] :   0   2   5
 [ 2 ] :   1   3   6
 [ 3 ] :   0   2   4   9
 [ 4 ] :   0   3
 [ 5 ] :   1
 [ 6 ] :   2   7   8
 [ 7 ] :   6
 [ 8 ] :   6
 [ 9 ] :   3   10   11
 [ 10 ] :   9   11
 [ 11 ] :   9   10
 No edge between vertices [ 4 - 7 ]
 Remove edge [ 3 - 9 ] disconnecting this graph
 Remove edge [ 1 - 2 ] not disconnecting this graph
 Remove edge [ 6 - 2 ] disconnecting this graph
 Remove edge [ 10 - 11 ] not disconnecting this graph
#    Ruby Program
#    Check if removing a given edge disconnects a graph
class Graph 
	# Define the accessor and reader of class Graph
	attr_reader :vertices, :adjacencylist
	attr_accessor :vertices, :adjacencylist
	#  Number of vertices in graph
	#  Use to collect edges information
	def initialize(vertices) 
		self.vertices = vertices
		self.adjacencylist = []
		i = 0
		while (i < self.vertices) 
			self.adjacencylist.push([])
			i += 1
		end

	end

	def addEdge(u, v) 
		if (u < 0 || u >= self.vertices || 
            v < 0 || v >= self.vertices) 
			return
		end

		#  Add node edge
		self.adjacencylist[u].push(v)
		self.adjacencylist[v].push(u)
	end

	#  Display graph nodes and edges
	def printGraph() 
		print("\n Graph Adjacency List ")
		i = 0
		while (i < self.vertices) 
			print(" \n [", i ,"] :")
			j = 0
			#  iterate edges of i node
			while (j < self.adjacencylist[i].length) 
				print("  ", self.adjacencylist[i][j])
				j += 1
			end

			i += 1
		end

	end

	def dfs(visited, start) 
		if (start < 0 || start >= self.vertices) 
			#  In case given invalid node
			return
		end

		#  Mark a current visited node
		visited[start] = true
		i = 0
		#  Execute edges of given start vertices
		while (i < self.adjacencylist[start].length) 
			if (visited[self.adjacencylist[start][i]] == false) 
				#  When edge node not visiting, then perform DFS operation
				self.dfs(visited, self.adjacencylist[start][i])
			end

			#  Visit to next node
			i += 1
		end

	end

	def edgePosition(u, v) 
		i = 0
		while (i < self.adjacencylist[u].length) 
			if (self.adjacencylist[u][i] == v) 
				return i
			end

			i += 1
		end

		return -1
	end

	def removeNodeEdge(u, v) 
		if (u < 0 || v < 0 || 
            u > self.vertices || v > self.vertices) 
			return false
		end

		a = self.edgePosition(u, v)
		b = self.edgePosition(v, u)
		if (a == -1 || b == -1) 
			#  Given edge are not exist between given nodes 
			return false
		end

		#  Remove edges
		self.adjacencylist[u].delete_at(a)
		self.adjacencylist[v].delete_at(b)
		return true
	end

	def unsetVisit(visited) 
		i = 0
		while (i < self.vertices) 
			visited[i] = false
			i += 1
		end

	end

	def isAllVerticesVisit(visited) 
		i = 0
		while (i < self.vertices) 
			if (visited[i] == false) 
				return false
			end

			i += 1
		end

		return true
	end

	def disconnectByEdge(u, v) 
		visited = Array.new(self.vertices) {false}
		self.unsetVisit(visited)
		self.dfs(visited, 0)
		if (self.isAllVerticesVisit(visited) == true) 
			if (self.removeNodeEdge(u, v) == true) 
				self.unsetVisit(visited)
				self.dfs(visited, 0)
				#  Add remove edge
				self.addEdge(u, v)
				if (self.isAllVerticesVisit(visited)) 
					#  not a bridge edge
					#  graph are not disconnect
					print("\n Remove edge [", 
                          u ,"-", v ,"] not disconnecting this graph ")
				else
 
					print("\n Remove edge [", 
                          u ,"-", v ,"] disconnecting this graph ")
				end

			else
 
				#  When edges are not exist
				print("\n No edge between vertices [", 
                      	u ,"-", v ,"]")
			end

		else
 
			#  When graph is already disconnected?
			print("\n Graph is already disconnected")
		end

	end

end

def main() 
	graph = Graph.new(12)
	graph.addEdge(0, 1)
	graph.addEdge(0, 3)
	graph.addEdge(0, 4)
	graph.addEdge(1, 2)
	graph.addEdge(1, 5)
	graph.addEdge(2, 3)
	graph.addEdge(2, 6)
	graph.addEdge(3, 4)
	graph.addEdge(3, 9)
	graph.addEdge(6, 7)
	graph.addEdge(6, 8)
	graph.addEdge(9, 10)
	graph.addEdge(9, 11)
	graph.addEdge(10, 11)
	#  Display graph element
	graph.printGraph()
	#  Test case
	graph.disconnectByEdge(4, 7)
	graph.disconnectByEdge(3, 9)
	graph.disconnectByEdge(1, 2)
	graph.disconnectByEdge(6, 2)
	graph.disconnectByEdge(10, 11)
end

main()

input

 Graph Adjacency List  
 [0] :  1  3  4 
 [1] :  0  2  5 
 [2] :  1  3  6 
 [3] :  0  2  4  9 
 [4] :  0  3 
 [5] :  1 
 [6] :  2  7  8 
 [7] :  6 
 [8] :  6 
 [9] :  3  10  11 
 [10] :  9  11 
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph 
 Remove edge [1-2] not disconnecting this graph 
 Remove edge [6-2] disconnecting this graph 
 Remove edge [10-11] not disconnecting this graph 
import scala.collection.mutable._;
/*
    Scala Program
    Check if removing a given edge disconnects a graph
*/
class Graph(
	// Number of vertices in graph
	var vertices: Int,
		// Use to collect edges information
		var adjacencylist: ArrayBuffer[ArrayBuffer[Int]])
{
	def this(vertices: Int)
	{
		this(vertices,new ArrayBuffer[ArrayBuffer[Int]](vertices));
		var i: Int = 0;
		while (i < this.vertices)
		{
			this.adjacencylist += new ArrayBuffer[Int]();
			i += 1;
		}
	}
	def addEdge(u: Int, v: Int): Unit = {
		if (u < 0 || u >= this.vertices || 
             v < 0 || v >= this.vertices)
		{
			return;
		}
		// Add node edge
		adjacencylist(u) += v;
		adjacencylist(v) += u;
	}
	// Display graph nodes and edges
	def printGraph(): Unit = {
		print("\n Graph Adjacency List ");
		var i: Int = 0;
		while (i < this.vertices)
		{
			print(" \n [" + i + "] :");
			var j: Int = 0;
			// iterate edges of i node
			while (j < this.adjacencylist(i).size)
			{
				print("  " + this.adjacencylist(i)(j));
				j += 1;
			}
			i += 1;
		}
	}
	def dfs(visited: Array[Boolean], start: Int): Unit = {
		if (start < 0 || start >= this.vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		visited(start) = true;
		var i: Int = 0;
		// Execute edges of given start vertices
		while (i < adjacencylist(start).size)
		{
			if (visited(adjacencylist(start)(i)) == false)
			{
				// When edge node not visiting, then perform DFS operation
				dfs(visited, adjacencylist(start)(i));
			}
			// Visit to next node
			i += 1;
		}
	}
	def edgePosition(u: Int, v: Int): Int = {
		var i: Int = 0;
		while (i < this.adjacencylist(u).size)
		{
			if (this.adjacencylist(u)(i) == v)
			{
				return i;
			}
			i += 1;
		}
		return -1;
	}
	def removeNodeEdge(u: Int, v: Int): Boolean = {
		if (u < 0 || v < 0 || u > this.vertices || v > this.vertices)
		{
			return false;
		}
		var a: Int = edgePosition(u, v);
		var b: Int = edgePosition(v, u);
		if (a == -1 || b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		this.adjacencylist(u).remove(a);
		this.adjacencylist(v).remove(b);
		return true;
	}
	def unsetVisit(visited: Array[Boolean]): Unit = {
		var i: Int = 0;
		while (i < this.vertices)
		{
			visited(i) = false;
			i += 1;
		}
	}
	def isAllVerticesVisit(visited: Array[Boolean]): Boolean = {
		var i: Int = 0;
		while (i < this.vertices)
		{
			if (visited(i) == false)
			{
				return false;
			}
			i += 1;
		}
		return true;
	}
	def disconnectByEdge(u: Int, v: Int): Unit = {
		var visited: Array[Boolean] = 
          Array.fill[Boolean](this.vertices)(false);
		unsetVisit(visited);
		dfs(visited, 0);
		if (isAllVerticesVisit(visited) == true)
		{
			if (removeNodeEdge(u, v) == true)
			{
				unsetVisit(visited);
				dfs(visited, 0);
				// Add remove edge
				addEdge(u, v);
				if (isAllVerticesVisit(visited))
				{
					// not a bridge edge
					// graph are not disconnect
					print("\n Remove edge [" + u + 
                          "-" + v + "] not disconnecting this graph ");
				}
				else
				{
					print("\n Remove edge [" + u + 
                          "-" + v + "] disconnecting this graph ");
				}
			}
			else
			{
				// When edges are not exist
				print("\n No edge between vertices [" + 
                      		u + "-" + v + "]");
			}
		}
		else
		{
			// When graph is already disconnected?
			print("\n Graph is already disconnected");
		}
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var graph: Graph = new Graph(12);
		graph.addEdge(0, 1);
		graph.addEdge(0, 3);
		graph.addEdge(0, 4);
		graph.addEdge(1, 2);
		graph.addEdge(1, 5);
		graph.addEdge(2, 3);
		graph.addEdge(2, 6);
		graph.addEdge(3, 4);
		graph.addEdge(3, 9);
		graph.addEdge(6, 7);
		graph.addEdge(6, 8);
		graph.addEdge(9, 10);
		graph.addEdge(9, 11);
		graph.addEdge(10, 11);
		// Display graph element
		graph.printGraph();
		// Test case
		graph.disconnectByEdge(4, 7);
		graph.disconnectByEdge(3, 9);
		graph.disconnectByEdge(1, 2);
		graph.disconnectByEdge(6, 2);
		graph.disconnectByEdge(10, 11);
	}
}

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph
import Foundation;
/*
    Swift 4 Program
    Check if removing a given edge disconnects a graph
*/
class Graph
{
	// Number of vertices in graph
	var vertices: Int;
	// Use to collect edges information
	var adjacencylist: [[Int]];
	init(_ vertices: Int)
	{
		self.vertices = vertices;
		self.adjacencylist = [[Int]]();
		var i: Int = 0;
		while (i < self.vertices)
		{
			self.adjacencylist.append([Int]());
			i += 1;
		}
	}
	func addEdge(_ u: Int, _ v: Int)
	{
		if (u < 0 || u >= self.vertices || 
            v < 0 || v >= self.vertices)
		{
			return;
		}
		// Add node edge
		self.adjacencylist[u].append(v);
		self.adjacencylist[v].append(u);
	}
	// Display graph nodes and edges
	func printGraph()
	{
		print("\n Graph Adjacency List ", terminator: "");
		var i: Int = 0;
		while (i < self.vertices)
		{
			print(" \n [", i ,"] :", terminator: "");
			var j: Int = 0;
			// iterate edges of i node
			while (j < self.adjacencylist[i].count)
			{
				print("  ", self.adjacencylist[i][j], terminator: "");
				j += 1;
			}
			i += 1;
		}
	}
	func dfs(_ visited: inout[Bool], _ start: Int)
	{
		if (start < 0 || start >= self.vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		visited[start] = true;
		var i: Int = 0;
		// Execute edges of given start vertices
		while (i < self.adjacencylist[start].count)
		{
			if (visited[self.adjacencylist[start][i]] == false)
			{
				// When edge node not visiting, then perform DFS operation
				self.dfs(&visited, self.adjacencylist[start][i]);
			}
			// Visit to next node
			i += 1;
		}
	}
	func edgePosition(_ u: Int, _ v: Int) -> Int
	{
		var i: Int = 0;
		while (i < self.adjacencylist[u].count)
		{
			if (self.adjacencylist[u][i] == v)
			{
				return i;
			}
			i += 1;
		}
		return -1;
	}
	func removeNodeEdge(_ u: Int, _ v: Int) -> Bool
	{
		if (u < 0 || v < 0 || u > self.vertices || v > self.vertices)
		{
			return false;
		}
		let a: Int = self.edgePosition(u, v);
		let b: Int = self.edgePosition(v, u);
		if (a == -1 || b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		self.adjacencylist[u].remove(at: a);
		self.adjacencylist[v].remove(at: b);
		return true;
	}
	func unsetVisit(_ visited: inout[Bool])
	{
		var i: Int = 0;
		while (i < self.vertices)
		{
			visited[i] = false;
			i += 1;
		}
	}
	func isAllVerticesVisit(_ visited: [Bool]) -> Bool
	{
		var i: Int = 0;
		while (i < self.vertices)
		{
			if (visited[i] == false)
			{
				return false;
			}
			i += 1;
		}
		return true;
	}
	func disconnectByEdge(_ u: Int, _ v: Int)
	{
		var visited: [Bool] = Array(repeating: false, count: self.vertices);
		self.dfs(&visited, 0);
		if (self.isAllVerticesVisit(visited) == true)
		{
			if (self.removeNodeEdge(u, v) == true)
			{
				self.unsetVisit(&visited);
				self.dfs(&visited, 0);
				// Add remove edge
				self.addEdge(u, v);
				if (self.isAllVerticesVisit(visited))
				{
					// not a bridge edge
					// graph are not disconnect
					print("\n Remove edge [", u ,
                          "-", v ,"] not disconnecting this graph ", 
                          terminator: "");
				}
				else
				{
					print("\n Remove edge [", 
                          u ,"-", v ,"] disconnecting this graph ", 
                          terminator: "");
				}
			}
			else
			{
				// When edges are not exist
				print("\n No edge between vertices [", 
                      u ,"-", v ,"]", terminator: "");
			}
		}
		else
		{
			// When graph is already disconnected?
			print("\n Graph is already disconnected", terminator: "");
		}
	}
}
func main()
{
	let graph: Graph = Graph(12);
	graph.addEdge(0, 1);
	graph.addEdge(0, 3);
	graph.addEdge(0, 4);
	graph.addEdge(1, 2);
	graph.addEdge(1, 5);
	graph.addEdge(2, 3);
	graph.addEdge(2, 6);
	graph.addEdge(3, 4);
	graph.addEdge(3, 9);
	graph.addEdge(6, 7);
	graph.addEdge(6, 8);
	graph.addEdge(9, 10);
	graph.addEdge(9, 11);
	graph.addEdge(10, 11);
	// Display graph element
	graph.printGraph();
	// Test case
	graph.disconnectByEdge(4, 7);
	graph.disconnectByEdge(3, 9);
	graph.disconnectByEdge(1, 2);
	graph.disconnectByEdge(6, 2);
	graph.disconnectByEdge(10, 11);
}
main();

input

 Graph Adjacency List
 [ 0 ] :   1   3   4
 [ 1 ] :   0   2   5
 [ 2 ] :   1   3   6
 [ 3 ] :   0   2   4   9
 [ 4 ] :   0   3
 [ 5 ] :   1
 [ 6 ] :   2   7   8
 [ 7 ] :   6
 [ 8 ] :   6
 [ 9 ] :   3   10   11
 [ 10 ] :   9   11
 [ 11 ] :   9   10
 No edge between vertices [ 4 - 7 ]
 Remove edge [ 3 - 9 ] disconnecting this graph
 Remove edge [ 1 - 2 ] not disconnecting this graph
 Remove edge [ 6 - 2 ] disconnecting this graph
 Remove edge [ 10 - 11 ] not disconnecting this graph
/*
    Kotlin Program
    Check if removing a given edge disconnects a graph
*/
class Graph
{
	// Number of vertices in graph
	var vertices: Int;
	// Use to collect edges information
	var adjacencylist: MutableList < MutableList < Int >>;
	constructor(vertices: Int)
	{
		this.vertices = vertices;
		this.adjacencylist =  mutableListOf<MutableList<Int>>();
		var i: Int = 0;
		while (i < this.vertices)
		{
			this.adjacencylist.add(mutableListOf < Int > ());
			i += 1;
		}
	}
	fun addEdge(u: Int, v: Int): Unit
	{
		if (u < 0 || u >= this.vertices || 
            v < 0 || v >= this.vertices)
		{
			return;
		}
		// Add node edge
		this.adjacencylist[u].add(v);
		this.adjacencylist[v].add(u);
	}
	// Display graph nodes and edges
	fun printGraph(): Unit
	{
		print("\n Graph Adjacency List ");
		var i: Int = 0;
		while (i < this.vertices)
		{
			print(" \n [" + i + "] :");
			var j: Int = 0;
			// iterate edges of i node
			while (j < this.adjacencylist[i].size)
			{
				print("  " + this.adjacencylist[i][j]);
				j += 1;
			}
			i += 1;
		}
	}
	fun dfs(visited: Array < Boolean > , start: Int): Unit
	{
		if (start < 0 || start >= this.vertices)
		{
			// In case given invalid node
			return;
		}
		// Mark a current visited node
		visited[start] = true;
		var i: Int = 0;
		// Execute edges of given start vertices
		while (i < this.adjacencylist[start].size)
		{
			if (visited[this.adjacencylist[start][i]] == false)
			{
				// When edge node not visiting, then perform DFS operation
				this.dfs(visited, this.adjacencylist[start][i]);
			}
			// Visit to next node
			i += 1;
		}
	}
	fun edgePosition(u: Int, v: Int): Int
	{
		var i: Int = 0;
		while (i < this.adjacencylist[u].size)
		{
			if (this.adjacencylist[u][i] == v)
			{
				return i;
			}
			i += 1;
		}
		return -1;
	}
	fun removeNodeEdge(u: Int, v: Int): Boolean
	{
		if (u < 0 || v < 0 || 
            u > this.vertices || v > this.vertices)
		{
			return false;
		}
		val a: Int = this.edgePosition(u, v);
		val b: Int = this.edgePosition(v, u);
		if (a == -1 || b == -1)
		{
			// Given edge are not exist between given nodes 
			return false;
		}
		// Remove edges
		this.adjacencylist[u].removeAt(a);
		this.adjacencylist[v].removeAt(b);
		return true;
	}
	fun unsetVisit(visited: Array < Boolean > ): Unit
	{
		var i: Int = 0;
		while (i < this.vertices)
		{
			visited[i] = false;
			i += 1;
		}
	}
	fun isAllVerticesVisit(visited: Array < Boolean > ): Boolean
	{
		var i: Int = 0;
		while (i < this.vertices)
		{
			if (visited[i] == false)
			{
				return false;
			}
			i += 1;
		}
		return true;
	}
	fun disconnectByEdge(u: Int, v: Int): Unit
	{
		val visited: Array < Boolean > = Array(this.vertices)
		{
			false
		};
		this.unsetVisit(visited);
		this.dfs(visited, 0);
		if (this.isAllVerticesVisit(visited) == true)
		{
			if (this.removeNodeEdge(u, v) == true)
			{
				this.unsetVisit(visited);
				this.dfs(visited, 0);
				// Add remove edge
				this.addEdge(u, v);
				if (this.isAllVerticesVisit(visited))
				{
					// not a bridge edge
					// graph are not disconnect
					print("\n Remove edge [" + u + 
                          "-" + v + "] not disconnecting this graph ");
				}
				else
				{
					print("\n Remove edge [" + u 
                          + "-" + v + "] disconnecting this graph ");
				}
			}
			else
			{
				// When edges are not exist
				print("\n No edge between vertices [" + u + 
                      "-" + v + "]");
			}
		}
		else
		{
			// When graph is already disconnected?
			print("\n Graph is already disconnected");
		}
	}
}
fun main(args: Array < String > ): Unit
{
	val graph: Graph = Graph(12);
	graph.addEdge(0, 1);
	graph.addEdge(0, 3);
	graph.addEdge(0, 4);
	graph.addEdge(1, 2);
	graph.addEdge(1, 5);
	graph.addEdge(2, 3);
	graph.addEdge(2, 6);
	graph.addEdge(3, 4);
	graph.addEdge(3, 9);
	graph.addEdge(6, 7);
	graph.addEdge(6, 8);
	graph.addEdge(9, 10);
	graph.addEdge(9, 11);
	graph.addEdge(10, 11);
	// Display graph element
	graph.printGraph();
	// Test case
	graph.disconnectByEdge(4, 7);
	graph.disconnectByEdge(3, 9);
	graph.disconnectByEdge(1, 2);
	graph.disconnectByEdge(6, 2);
	graph.disconnectByEdge(10, 11);
}

input

 Graph Adjacency List
 [0] :  1  3  4
 [1] :  0  2  5
 [2] :  1  3  6
 [3] :  0  2  4  9
 [4] :  0  3
 [5] :  1
 [6] :  2  7  8
 [7] :  6
 [8] :  6
 [9] :  3  10  11
 [10] :  9  11
 [11] :  9  10
 No edge between vertices [4-7]
 Remove edge [3-9] disconnecting this graph
 Remove edge [1-2] not disconnecting this graph
 Remove edge [6-2] disconnecting this graph
 Remove edge [10-11] not disconnecting this graph


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