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Find the first non-repeating character of string

Here given code implementation process.

/*
  Java Program for 
  Find the first non-repeating character of string
*/
public class Frequency
{
	void firstNonRepeat(String text)
	{
		System.out.println(" Given text : " + text);
		// Used to collect character frequency
		int[] count = new int[256];
		// Loop controlling variable
		int i;
		// Set initial character frequency
		for (i = 0; i < 256; i++)
		{
			count[i] = 0;
		}
		// Count character frequency
		for (i = 0; i < text.length(); i++)
		{
			count[text.charAt(i)]++;
		}
		// Find first non-repeating character
		for (i = 0; i < text.length(); i++)
		{
			if (count[text.charAt(i)] == 1)
			{
				// When we get first non-repeating character
				System.out.print(" First non-repeating character : ");
				System.out.println(text.charAt(i));
				return;
			}
		}
		// When string contains duplicate characters
		System.out.println(" First non-repeating character not exist ");
	}
	public static void main(String[] args)
	{
		Frequency task = new Frequency();
		// Test Case
		task.firstNonRepeat("abcaXbyyz");
		task.firstNonRepeat("aeabbccefzs");
		task.firstNonRepeat("abcxyzzabxcy");
		task.firstNonRepeat("a+b/a-c");
	}
}

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
// Include header file
#include <iostream>

#include <string>

using namespace std;
/*
  C++ Program for 
  Find the first non-repeating character of string
*/
class Frequency
{
	public: void firstNonRepeat(string text)
	{
		cout << " Given text : " << text << endl;
		// Used to collect character frequency
		int count[256];
		// Loop controlling variable
		int i;
		// Set initial character frequency
		for (i = 0; i < 256; i++)
		{
			count[i] = 0;
		}
		// Count character frequency
		for (i = 0; i < text.length(); i++)
		{
			count[text[i]]++;
		}
		// Find first non-repeating character
		for (i = 0; i < text.length(); i++)
		{
			if (count[text[i]] == 1)
			{
				// When we get first non-repeating character
				cout << " First non-repeating character : ";
				cout << text[i] << endl;
				return;
			}
		}
		// When string contains duplicate characters
		cout << " First non-repeating character not exist " << endl;
	}
};
int main()
{
	Frequency *task = new Frequency();
	// Test Case
	task->firstNonRepeat("abcaXbyyz");
	task->firstNonRepeat("aeabbccefzs");
	task->firstNonRepeat("abcxyzzabxcy");
	task->firstNonRepeat("a+b/a-c");
	return 0;
}

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
// Include namespace system
using System;
/*
  Csharp Program for 
  Find the first non-repeating character of string
*/
public class Frequency
{
	void firstNonRepeat(String text)
	{
		Console.WriteLine(" Given text : " + text);
		// Used to collect character frequency
		int[] count = new int[256];
		// Loop controlling variable
		int i;
		// Set initial character frequency
		for (i = 0; i < 256; i++)
		{
			count[i] = 0;
		}
		// Count character frequency
		for (i = 0; i < text.Length; i++)
		{
			count[text[i]]++;
		}
		// Find first non-repeating character
		for (i = 0; i < text.Length; i++)
		{
			if (count[text[i]] == 1)
			{
				// When we get first non-repeating character
				Console.Write(" First non-repeating character : ");
				Console.WriteLine(text[i]);
				return;
			}
		}
		// When string contains duplicate characters
		Console.WriteLine(" First non-repeating character not exist ");
	}
	public static void Main(String[] args)
	{
		Frequency task = new Frequency();
		// Test Case
		task.firstNonRepeat("abcaXbyyz");
		task.firstNonRepeat("aeabbccefzs");
		task.firstNonRepeat("abcxyzzabxcy");
		task.firstNonRepeat("a+b/a-c");
	}
}

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
<?php
/*
  Php Program for 
  Find the first non-repeating character of string
*/
class Frequency
{
	function firstNonRepeat($text)
	{
		echo " Given text : ".$text.
		"\n";
		// Used to collect character frequency
		$count = array_fill(0, 256, 0);
		// Loop controlling variable
		$i = 0;
		// Count character frequency
		for ($i = 0; $i < strlen($text); $i++)
		{
			$count[ord($text[$i])]++;
		}
		// Find first non-repeating character
		for ($i = 0; $i < strlen($text); $i++)
		{
			if ($count[ord($text[$i])] == 1)
			{
				// When we get first non-repeating character
				echo " First non-repeating character : ";
				echo $text[$i]."\n";
				return;
			}
		}
		// When string contains duplicate characters
		echo " First non-repeating character not exist ".
		"\n";
	}
}

function main()
{
	$task = new Frequency();
	// Test Case
	$task->firstNonRepeat("abcaXbyyz");
	$task->firstNonRepeat("aeabbccefzs");
	$task->firstNonRepeat("abcxyzzabxcy");
	$task->firstNonRepeat("a+b/a-c");
}
main();

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
/*
  Node JS Program for 
  Find the first non-repeating character of string
*/
class Frequency
{
	firstNonRepeat(text)
	{
		console.log(" Given text : " + text);
		// Used to collect character frequency
		var count = Array(256).fill(0);
		// Loop controlling variable
		var i = 0;
		// Count character frequency
		for (i = 0; i < text.length; i++)
		{
			count[text.charCodeAt(i)]++;
		}
		// Find first non-repeating character
		for (i = 0; i < text.length; i++)
		{
			if (count[text.charCodeAt(i)] == 1)
			{
				// When we get first non-repeating character
				process.stdout.write(" First non-repeating character : ");
				console.log(text.charAt(i));
				return;
			}
		}
		// When string contains duplicate characters
		console.log(" First non-repeating character not exist ");
	}
}

function main()
{
	var task = new Frequency();
	// Test Case
	task.firstNonRepeat("abcaXbyyz");
	task.firstNonRepeat("aeabbccefzs");
	task.firstNonRepeat("abcxyzzabxcy");
	task.firstNonRepeat("a+b/a-c");
}
main();

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
#  Python 3 Program for 
#  Find the first non-repeating character of string
class Frequency :
	def firstNonRepeat(self, text) :
		print(" Given text : ", text)
		count = [0] * (256)
		i = 0
		#  Count character frequency
		i = 0
		while (i < len(text)) :
			count[ord(text[i])] += 1
			i += 1
		
		#  Find first non-repeating character
		i = 0
		while (i < len(text)) :
			if (count[ord(text[i])] == 1) :
				#  When we get first non-repeating character
				print(" First non-repeating character : ", end = "")
				print(text[i])
				return
			
			i += 1
		
		#  When string contains duplicate characters
		print(" First non-repeating character not exist ")
	

def main() :
	task = Frequency()
	#  Test Case
	task.firstNonRepeat("abcaXbyyz")
	task.firstNonRepeat("aeabbccefzs")
	task.firstNonRepeat("abcxyzzabxcy")
	task.firstNonRepeat("a+b/a-c")

if __name__ == "__main__": main()

input

 Given text :  abcaXbyyz
 First non-repeating character : c
 Given text :  aeabbccefzs
 First non-repeating character : f
 Given text :  abcxyzzabxcy
 First non-repeating character not exist
 Given text :  a+b/a-c
 First non-repeating character : +
#  Ruby Program for 
#  Find the first non-repeating character of string
class Frequency 
	def firstNonRepeat(text) 
		print(" Given text : ", text, "\n")
		#  Used to collect character frequency
		count = Array.new(256) {0}
		#  Loop controlling variable
		i = 0
		#  Count character frequency
		i = 0
		while (i < text.length) 
			count[text[i].ord] += 1
			i += 1
		end

		#  Find first non-repeating character
		i = 0
		while (i < text.length) 
			if (count[text[i].ord] == 1) 
				#  When we get first non-repeating character
				print(" First non-repeating character : ")
				print(text[i], "\n")
				return
			end

			i += 1
		end

		#  When string contains duplicate characters
		print(" First non-repeating character not exist ", "\n")
	end

end

def main() 
	task = Frequency.new()
	#  Test Case
	task.firstNonRepeat("abcaXbyyz")
	task.firstNonRepeat("aeabbccefzs")
	task.firstNonRepeat("abcxyzzabxcy")
	task.firstNonRepeat("a+b/a-c")
end

main()

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist 
 Given text : a+b/a-c
 First non-repeating character : +

/*
  Scala Program for 
  Find the first non-repeating character of string
*/
class Frequency()
{
	def firstNonRepeat(text: String): Unit = {
		println(" Given text : " + text);
		// Used to collect character frequency
		var count: Array[Int] = Array.fill[Int](256)(0);
		// Loop controlling variable
		var i: Int = 0;
		// Count character frequency
		i = 0;
		while (i < text.length())
		{
			count(text.charAt(i).toInt) += 1;
			i += 1;
		}
		// Find first non-repeating character
		i = 0;
		while (i < text.length())
		{
			if (count(text.charAt(i).toInt) == 1)
			{
				// When we get first non-repeating character
				print(" First non-repeating character : ");
				println(text.charAt(i));
				return;
			}
			i += 1;
		}
		// When string contains duplicate characters
		println(" First non-repeating character not exist ");
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var task: Frequency = new Frequency();
		// Test Case
		task.firstNonRepeat("abcaXbyyz");
		task.firstNonRepeat("aeabbccefzs");
		task.firstNonRepeat("abcxyzzabxcy");
		task.firstNonRepeat("a+b/a-c");
	}
}

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
/*
  Swift 4 Program for 
  Find the first non-repeating character of string
*/
class Frequency
{
	func firstNonRepeat(_ data: String)
	{
        let text = Array(data);
		print(" Given text : ", data);
		// Used to collect character frequency
		var count: [Int] = Array(repeating: 0, count: 256);
		// Loop controlling variable
		var i: Int = 0;
		// Count character frequency
		while (i < text.count)
		{
            let position = Int(UnicodeScalar(String(text[i]))!.value);
			count[position] += 1;
			i += 1;
		}
		// Find first non-repeating character
		i = 0;
		while (i < text.count)
		{
          	let position = Int(UnicodeScalar(String(text[i]))!.value);
			if (count[position] == 1)
			{
				// When we get first non-repeating character
				print(" First non-repeating character : ", terminator: "");
				print(text[i]);
				return;
			}
			i += 1;
		}
		// When string contains duplicate characters
		print(" First non-repeating character not exist ");
	}
}
func main()
{
	let task: Frequency = Frequency();
	// Test Case
	task.firstNonRepeat("abcaXbyyz");
	task.firstNonRepeat("aeabbccefzs");
	task.firstNonRepeat("abcxyzzabxcy");
	task.firstNonRepeat("a+b/a-c");
}
main();

input

 Given text :  abcaXbyyz
 First non-repeating character : c
 Given text :  aeabbccefzs
 First non-repeating character : f
 Given text :  abcxyzzabxcy
 First non-repeating character not exist
 Given text :  a+b/a-c
 First non-repeating character : +
/*
  Kotlin Program for 
  Find the first non-repeating character of string
*/
class Frequency
{
	fun firstNonRepeat(text: String): Unit
	{
		println(" Given text : " + text);
		// Used to collect character frequency
		val count: Array < Int > = Array(256)
		{
			0
		};
		// Loop controlling variable
		var i: Int = 0;
		while (i < text.length)
		{
			count[text.get(i).toInt()] += 1;
			i += 1;
		}
		i = 0;
		while (i < text.length)
		{
			if (count[text.get(i).toInt()] == 1)
			{
				// When we get first non-repeating character
				print(" First non-repeating character : ");
				println(text.get(i));
				return;
			}
			i += 1;
		}
		// When string contains duplicate characters
		println(" First non-repeating character not exist ");
	}
}
fun main(args: Array < String > ): Unit
{
	val task: Frequency = Frequency();
	// Test Case
	task.firstNonRepeat("abcaXbyyz");
	task.firstNonRepeat("aeabbccefzs");
	task.firstNonRepeat("abcxyzzabxcy");
	task.firstNonRepeat("a+b/a-c");
}

input

 Given text : abcaXbyyz
 First non-repeating character : c
 Given text : aeabbccefzs
 First non-repeating character : f
 Given text : abcxyzzabxcy
 First non-repeating character not exist
 Given text : a+b/a-c
 First non-repeating character : +
Last updated on by Kalkicode




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