# Count subarrays with equal number of 1’s and 0’s

Here given code implementation process.

``````// C Program
// Count subarrays with equal number of 1’s and 0’s
#include <stdio.h>

// Display array elements
void printArr(int arr[], int n)
{
for (int i = 0; i < n; ++i)
{
printf("  %d", arr[i]);
}
printf("\n");
}
void countSame0s1s(int arr[], int n)
{
int count = 0;
int result = 0;
// This is used to collect information of subarray
// of zero and ones
int dp[n][2];
for (int i = 0; i < n; ++i)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i][0] = 0;
dp[i][1] = 0;
}
dp[0][0] = 1;
// Calculate subarray with equal number of 0s and 1s
for (int i = 0; i < n; ++i)
{
if (arr[i] == 0)
{
count++;
}
else
{
count--;
}
if (count < 0)
{
result += dp[-count][1];
dp[-count][1] += 1;
}
else
{
result += dp[count][0];
dp[count][0] += 1;
}
}
printArr(arr, n);
printf(" Result : %d \n", result);
}
int main()
{
// Sorted Arrays
int a[] = {
0 , 1 , 0 , 1
};
int b[] = {
1 , 1 , 1 , 0 , 1 , 0 , 1 , 0
};
int c[] = {
1 , 1 , 0 , 1
};
// Get the size
int l1 = sizeof(a) / sizeof(a[0]);
int l2 = sizeof(b) / sizeof(b[0]);
int l3 = sizeof(c) / sizeof(c[0]);
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
countSame0s1s(a, l1);
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
countSame0s1s(b, l2);
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
countSame0s1s(c, l3);
return 0;
}``````

#### Output

``````  0  1  0  1
Result : 4
1  1  1  0  1  0  1  0
Result : 9
1  1  0  1
Result : 2``````
``````/*
Java Program
Count subarrays with equal number of 1’s and 0’s
*/
public class Subarrays
{
// Display array elements
public void printArr(int[] arr, int n)
{
for (int i = 0; i < n; ++i)
{
System.out.print(" " + arr[i] );
}
System.out.print("\n");
}
public void countSame0s1s(int[] arr, int n)
{
int count = 0;
int result = 0;
// This is used to collect information of subarray
// of zero and ones
int[][] dp = new int[n][2];
for (int i = 0; i < n; ++i)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i][0] = 0;
dp[i][1] = 0;
}
dp[0][0] = 1;
// Calculate subarray with equal number of 0s and 1s
for (int i = 0; i < n; ++i)
{
if (arr[i] == 0)
{
count++;
}
else
{
count--;
}
if (count < 0)
{
result += dp[-count][1];
dp[-count][1] += 1;
}
else
{
result += dp[count][0];
dp[count][0] += 1;
}
}
printArr(arr, n);
System.out.print(" Result : " + result + " \n");
}
public static void main(String[] args)
{
// Sorted Arrays
int[] a = {
0 , 1 , 0 , 1
};
int[] b = {
1 , 1 , 1 , 0 , 1 , 0 , 1 , 0
};
int[] c = {
1 , 1 , 0 , 1
};
// Get the size
int l1 = a.length;
int l2 = b.length;
int l3 = c.length;
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}
}``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````// Include header file
#include <iostream>
using namespace std;
/*
C++ Program
Count subarrays with equal number of 1’s and 0’s
*/
class Subarrays
{
public:
// Display array elements
void printArr(int arr[], int n)
{
for (int i = 0; i < n; ++i)
{
cout << " " << arr[i];
}
cout << "\n";
}
void countSame0s1s(int arr[], int n)
{
int count = 0;
int result = 0;
// This is used to collect information of subarray
// of zero and ones
int dp[n][2];
for (int i = 0; i < n; ++i)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i][0] = 0;
dp[i][1] = 0;
}
dp[0][0] = 1;
// Calculate subarray with equal number of 0s and 1s
for (int i = 0; i < n; ++i)
{
if (arr[i] == 0)
{
count++;
}
else
{
count--;
}
if (count < 0)
{
result += dp[-count][1];
dp[-count][1] += 1;
}
else
{
result += dp[count][0];
dp[count][0] += 1;
}
}
this->printArr(arr, n);
cout << " Result : " << result << " \n";
}
};
int main()
{
// Sorted Arrays
int a[] = {
0 , 1 , 0 , 1
};
int b[] = {
1 , 1 , 1 , 0 , 1 , 0 , 1 , 0
};
int c[] = {
1 , 1 , 0 , 1
};
// Get the size
int l1 = sizeof(a) / sizeof(a[0]);
int l2 = sizeof(b) / sizeof(b[0]);
int l3 = sizeof(c) / sizeof(c[0]);
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
return 0;
}``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````// Include namespace system
using System;
/*
Csharp Program
Count subarrays with equal number of 1’s and 0’s
*/
public class Subarrays
{
// Display array elements
public void printArr(int[] arr, int n)
{
for (int i = 0; i < n; ++i)
{
Console.Write(" " + arr[i]);
}
Console.Write("\n");
}
public void countSame0s1s(int[] arr, int n)
{
int count = 0;
int result = 0;
// This is used to collect information of subarray
// of zero and ones
int[,] dp = new int[n,2];
for (int i = 0; i < n; ++i)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i,0] = 0;
dp[i,1] = 0;
}
dp[0,0] = 1;
// Calculate subarray with equal number of 0s and 1s
for (int i = 0; i < n; ++i)
{
if (arr[i] == 0)
{
count++;
}
else
{
count--;
}
if (count < 0)
{
result += dp[-count,1];
dp[-count,1] += 1;
}
else
{
result += dp[count,0];
dp[count,0] += 1;
}
}
this.printArr(arr, n);
Console.Write(" Result : " + result + " \n");
}
public static void Main(String[] args)
{
// Sorted Arrays
int[] a = {
0 , 1 , 0 , 1
};
int[] b = {
1 , 1 , 1 , 0 , 1 , 0 , 1 , 0
};
int[] c = {
1 , 1 , 0 , 1
};
// Get the size
int l1 = a.Length;
int l2 = b.Length;
int l3 = c.Length;
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}
}``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````package main
import "fmt"
/*
Go Program
Count subarrays with equal number of 1’s and 0’s
*/

// Display array elements
func printArr(arr[] int, n int) {
for i := 0 ; i < n ; i++ {
fmt.Print(" ", arr[i])
}
fmt.Print("\n")
}
func countSame0s1s(arr[] int, n int) {
var count int = 0
var result int = 0
// This is used to collect information of subarray
// of zero and ones
var dp = make([][] int, n)
for i := 0; i < n; i++{
dp[i] = make([]int,2)
}
for i := 0 ; i < n ; i++ {
if arr[i] > 1 || arr[i] < 0 {
// Array not contain 0 and 1
return
}
dp[i][0] = 0
dp[i][1] = 0
}
dp[0][0] = 1
// Calculate subarray with equal number of 0s and 1s
for i := 0 ; i < n ; i++ {
if arr[i] == 0 {
count++
} else {
count--
}
if count < 0 {
result += dp[-count][1]
dp[-count][1] += 1
} else {
result += dp[count][0]
dp[count][0] += 1
}
}
printArr(arr, n)
fmt.Print(" Result : ", result, " \n")
}
func main() {

// Sorted Arrays
var a = [] int {
0,
1,
0,
1,
}
var b = [] int {
1,
1,
1,
0,
1,
0,
1,
0,
}
var c = [] int {
1,
1,
0,
1,
}
// Get the size
var l1 int = len(a)
var l2 int = len(b)
var l3 int = len(c)
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
countSame0s1s(a, l1)
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
countSame0s1s(b, l2)
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
countSame0s1s(c, l3)
}``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````<?php
/*
Php Program
Count subarrays with equal number of 1’s and 0’s
*/
class Subarrays
{
// Display array elements
public	function printArr(\$arr, \$n)
{
for (\$i = 0; \$i < \$n; ++\$i)
{
echo(" ".\$arr[\$i]);
}
echo("\n");
}
public	function countSame0s1s(\$arr, \$n)
{
\$count = 0;
\$result = 0;
// This is used to collect information of subarray
// of zero and ones
\$dp = array_fill(0, \$n, array_fill(0, 2, 0));
for (\$i = 0; \$i < \$n; ++\$i)
{
if (\$arr[\$i] > 1 || \$arr[\$i] < 0)
{
// Array not contain 0 and 1
return;
}
\$dp[\$i][0] = 0;
\$dp[\$i][1] = 0;
}
\$dp[0][0] = 1;
// Calculate subarray with equal number of 0s and 1s
for (\$i = 0; \$i < \$n; ++\$i)
{
if (\$arr[\$i] == 0)
{
\$count++;
}
else
{
\$count--;
}
if (\$count < 0)
{
\$result += \$dp[-\$count][1];
\$dp[-\$count][1] += 1;
}
else
{
\$result += \$dp[\$count][0];
\$dp[\$count][0] += 1;
}
}
\$this->printArr(\$arr, \$n);
echo(" Result : ".\$result." \n");
}
}

function main()
{
// Sorted Arrays
\$a = array(0, 1, 0, 1);
\$b = array(1, 1, 1, 0, 1, 0, 1, 0);
\$c = array(1, 1, 0, 1);
// Get the size
\$l1 = count(\$a);
\$l2 = count(\$b);
\$l3 = count(\$c);
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}
main();``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````/*
Node JS Program
Count subarrays with equal number of 1’s and 0’s
*/
class Subarrays
{
// Display array elements
printArr(arr, n)
{
for (var i = 0; i < n; ++i)
{
process.stdout.write(" " + arr[i]);
}
process.stdout.write("\n");
}
countSame0s1s(arr, n)
{
var count = 0;
var result = 0;
// This is used to collect information of subarray
// of zero and ones
var dp = Array(n).fill(0).map(() => new Array(2).fill(0));
for (var i = 0; i < n; ++i)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i][0] = 0;
dp[i][1] = 0;
}
dp[0][0] = 1;
// Calculate subarray with equal number of 0s and 1s
for (var i = 0; i < n; ++i)
{
if (arr[i] == 0)
{
count++;
}
else
{
count--;
}
if (count < 0)
{
result += dp[-count][1];
dp[-count][1] += 1;
}
else
{
result += dp[count][0];
dp[count][0] += 1;
}
}
this.printArr(arr, n);
process.stdout.write(" Result : " + result + " \n");
}
}

function main()
{
// Sorted Arrays
var a = [0, 1, 0, 1];
var b = [1, 1, 1, 0, 1, 0, 1, 0];
var c = [1, 1, 0, 1];
// Get the size
var l1 = a.length;
var l2 = b.length;
var l3 = c.length;
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}
main();``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````#    Python 3 Program
#    Count subarrays with equal number of 1’s and 0’s
class Subarrays :
#  Display list elements
def printArr(self, arr, n) :
i = 0
while (i < n) :
print(" ", arr[i], end = "")
i += 1

print(end = "\n")

def countSame0s1s(self, arr, n) :
count = 0
result = 0
#  This is used to collect information of sublist
#  of zero and ones
dp = [[0] * (2) for _ in range(n) ]
i = 0
while (i < n) :
if (arr[i] > 1 or arr[i] < 0) :
#  Array not contain 0 and 1
return

dp[i][0] = 0
dp[i][1] = 0
i += 1

dp[0][0] = 1
i = 0
#  Calculate sublist with equal number of 0s and 1s
while (i < n) :
if (arr[i] == 0) :
count += 1
else :
count -= 1

if (count < 0) :
result += dp[-count][1]
dp[-count][1] += 1
else :
result += dp[count][0]
dp[count][0] += 1

i += 1

self.printArr(arr, n)
print(" Result : ", result ," ")

def main() :
#  Sorted Arrays
a = [0, 1, 0, 1]
b = [1, 1, 1, 0, 1, 0, 1, 0]
c = [1, 1, 0, 1]
#  Get the size
l1 = len(a)
l2 = len(b)
l3 = len(c)
#  Test A
#  arr = [0, 1, 0,1]
#  --------------------------
#   ➀  [0, 1, 0, 1]
#   ➁        [0, 1]
#   ➂  [0, 1]
#   ➃     [1, 0]
#  ---------------
#   Total : 4
#  Test B
#  arr = [1, 1, 1, 0, 1, 0, 1, 0]
#  --------------------------
#   ➀          [1, 0]
#   ➁             [0, 1]
#   ➂                [1, 0]
#   ➃                   [0, 1]
#   ➄                      [1, 0]
#   ➅                [1, 0, 1, 0]
#   ➆          [1, 0, 1, 0, 1, 0]
#   ➇          [1, 0, 1, 0]
#   ➈             [0, 1, 0, 1]
#  -------------------------------
#   Total : 9
#  Test C
#  arr = [1, 1, 0, 1]
#  --------------------------
#   ➀       [1, 0]
#   ➁          [0, 1]
#  ---------------
#   Total : 2

if __name__ == "__main__": main()``````

#### Output

``````  0  1  0  1
Result :  4
1  1  1  0  1  0  1  0
Result :  9
1  1  0  1
Result :  2``````
``````#    Ruby Program
#    Count subarrays with equal number of 1’s and 0’s
class Subarrays
#  Display array elements
def printArr(arr, n)
i = 0
while (i < n)
print(" ", arr[i])
i += 1
end

print("\n")
end

def countSame0s1s(arr, n)
count = 0
result = 0
#  This is used to collect information of subarray
#  of zero and ones
dp = Array.new(n) {Array.new(2) {0}}
i = 0
while (i < n)
if (arr[i] > 1 || arr[i] < 0)
#  Array not contain 0 and 1
return
end

dp[i][0] = 0
dp[i][1] = 0
i += 1
end

dp[0][0] = 1
i = 0
#  Calculate subarray with equal number of 0s and 1s
while (i < n)
if (arr[i] == 0)
count += 1
else

count -= 1
end

if (count < 0)
result += dp[-count][1]
dp[-count][1] += 1
else

result += dp[count][0]
dp[count][0] += 1
end

i += 1
end

self.printArr(arr, n)
print(" Result : ", result ," \n")
end

end

def main()
#  Sorted Arrays
a = [0, 1, 0, 1]
b = [1, 1, 1, 0, 1, 0, 1, 0]
c = [1, 1, 0, 1]
#  Get the size
l1 = a.length
l2 = b.length
l3 = c.length
#  Test A
#  arr = [0, 1, 0,1]
#  --------------------------
#   ➀  [0, 1, 0, 1]
#   ➁        [0, 1]
#   ➂  [0, 1]
#   ➃     [1, 0]
#  ---------------
#   Total : 4
#  Test B
#  arr = [1, 1, 1, 0, 1, 0, 1, 0]
#  --------------------------
#   ➀          [1, 0]
#   ➁             [0, 1]
#   ➂                [1, 0]
#   ➃                   [0, 1]
#   ➄                      [1, 0]
#   ➅                [1, 0, 1, 0]
#   ➆          [1, 0, 1, 0, 1, 0]
#   ➇          [1, 0, 1, 0]
#   ➈             [0, 1, 0, 1]
#  ------------------------------
#   Total : 9
#  Test C
#  arr = [1, 1, 0, 1]
#  --------------------------
#   ➀       [1, 0]
#   ➁          [0, 1]
#  ---------------
#   Total : 2
end

main()``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2
``````
``````/*
Scala Program
Count subarrays with equal number of 1’s and 0’s
*/
class Subarrays()
{
// Display array elements
def printArr(arr: Array[Int], n: Int): Unit = {
var i: Int = 0;
while (i < n)
{
print(" " + arr(i));
i += 1;
}
print("\n");
}
def countSame0s1s(arr: Array[Int], n: Int): Unit = {
var count: Int = 0;
var result: Int = 0;
// This is used to collect information of subarray
// of zero and ones
var dp: Array[Array[Int]] = Array.fill[Int](n, 2)(0);
var i: Int = 0;
while (i < n)
{
if (arr(i) > 1 || arr(i) < 0)
{
// Array not contain 0 and 1
return;
}
dp(i)(0) = 0;
dp(i)(1) = 0;
i += 1;
}
dp(0)(0) = 1;
i = 0;
// Calculate subarray with equal number of 0s and 1s
while (i < n)
{
if (arr(i) == 0)
{
count += 1;
}
else
{
count -= 1;
}
if (count < 0)
{
result += dp(-count)(1);
dp(-count)(1) += 1;
}
else
{
result += dp(count)(0);
dp(count)(0) += 1;
}
i += 1;
}
printArr(arr, n);
print(" Result : " + result + " \n");
}
}
object Main
{
def main(args: Array[String]): Unit = {
var task: Subarrays = new Subarrays();
// Sorted Arrays
var a: Array[Int] = Array(0, 1, 0, 1);
var b: Array[Int] = Array(1, 1, 1, 0, 1, 0, 1, 0);
var c: Array[Int] = Array(1, 1, 0, 1);
// Get the size
var l1: Int = a.length;
var l2: Int = b.length;
var l3: Int = c.length;
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}
}``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````
``````import Foundation;
/*
Swift 4 Program
Count subarrays with equal number of 1’s and 0’s
*/
class Subarrays
{
// Display array elements
func printArr(_ arr: [Int], _ n: Int)
{
var i: Int = 0;
while (i < n)
{
print(" ", arr[i], terminator: "");
i += 1;
}
print(terminator: "\n");
}
func countSame0s1s(_ arr: [Int], _ n: Int)
{
var count: Int = 0;
var result: Int = 0;
// This is used to collect information of subarray
// of zero and ones
var dp: [
[Int]
] = Array(repeating: Array(repeating: 0, count: 2), count: n);
var i: Int = 0;
while (i < n)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i][0] = 0;
dp[i][1] = 0;
i += 1;
}
dp[0][0] = 1;
i = 0;
// Calculate subarray with equal number of 0s and 1s
while (i < n)
{
if (arr[i] == 0)
{
count += 1;
}
else
{
count -= 1;
}
if (count < 0)
{
result += dp[-count][1];
dp[-count][1] += 1;
}
else
{
result += dp[count][0];
dp[count][0] += 1;
}
i += 1;
}
self.printArr(arr, n);
print(" Result : ", result ," ");
}
}
func main()
{
// Sorted Arrays
let a: [Int] = [0, 1, 0, 1];
let b: [Int] = [1, 1, 1, 0, 1, 0, 1, 0];
let c: [Int] = [1, 1, 0, 1];
// Get the size
let l1: Int = a.count;
let l2: Int = b.count;
let l3: Int = c.count;
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}
main();``````

#### Output

``````  0  1  0  1
Result :  4
1  1  1  0  1  0  1  0
Result :  9
1  1  0  1
Result :  2``````
``````/*
Kotlin Program
Count subarrays with equal number of 1’s and 0’s
*/
class Subarrays
{
// Display array elements
fun printArr(arr: Array < Int > , n: Int): Unit
{
var i: Int = 0;
while (i < n)
{
print(" " + arr[i]);
i += 1;
}
print("\n");
}
fun countSame0s1s(arr: Array < Int > , n: Int): Unit
{
var count: Int = 0;
var result: Int = 0;
// This is used to collect information of subarray
// of zero and ones
val dp: Array < Array < Int >> = Array(n)
{
Array(2)
{
0
}
};
var i: Int = 0;
while (i < n)
{
if (arr[i] > 1 || arr[i] < 0)
{
// Array not contain 0 and 1
return;
}
dp[i][0] = 0;
dp[i][1] = 0;
i += 1;
}
dp[0][0] = 1;
i = 0;
// Calculate subarray with equal number of 0s and 1s
while (i < n)
{
if (arr[i] == 0)
{
count += 1;
}
else
{
count -= 1;
}
if (count < 0)
{
result += dp[-count][1];
dp[-count][1] += 1;
}
else
{
result += dp[count][0];
dp[count][0] += 1;
}
i += 1;
}
this.printArr(arr, n);
print(" Result : " + result + " \n");
}
}
fun main(args: Array < String > ): Unit
{
// Sorted Arrays
val a: Array < Int > = arrayOf(0, 1, 0, 1);
val b: Array < Int > = arrayOf(1, 1, 1, 0, 1, 0, 1, 0);
val c: Array < Int > = arrayOf(1, 1, 0, 1);
// Get the size
val l1: Int = a.count();
val l2: Int = b.count();
val l3: Int = c.count();
// Test A
// arr = [0, 1, 0,1]
// --------------------------
//
//  ➀  [0, 1, 0, 1]
//  ➁        [0, 1]
//  ➂  [0, 1]
//  ➃     [1, 0]
// ---------------
//  Total : 4
// Test B
// arr = [1, 1, 1, 0, 1, 0, 1, 0]
// --------------------------
//  ➀          [1, 0]
//  ➁             [0, 1]
//  ➂                [1, 0]
//  ➃                   [0, 1]
//  ➄                      [1, 0]
//  ➅                [1, 0, 1, 0]
//  ➆          [1, 0, 1, 0, 1, 0]
//  ➇          [1, 0, 1, 0]
//  ➈             [0, 1, 0, 1]
// ---------------
//  Total : 9
// Test C
// arr = [1, 1, 0, 1]
// --------------------------
//  ➀       [1, 0]
//  ➁          [0, 1]
// ---------------
//  Total : 2
}``````

#### Output

`````` 0 1 0 1
Result : 4
1 1 1 0 1 0 1 0
Result : 9
1 1 0 1
Result : 2``````

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