Given an array of N positive elements. The task is to find an element which is equal to the sum of all elements of array except itself.**Examples:**

Input:arr[] = {1, 2, 3, 6}Output:6 6 is the element which is equal to the sum of all remaining elements i.e. 1 + 2+ 3 = 6Input:arr[] = {2, 2, 2, 2}Output:-1

**Approach:** First of all, find the sum of all elements of an array. Then iterate over each element and check the condition that if **(a[i] == sum-a[i] )**. If true then print that **a[i]**, else print “-1” if no such element found.

Below is the implementation of the above approach:

## C++

`// C++ implementation of the above approach` `#include <bits/stdc++.h>` `#define ll long long int` `using` `namespace` `std;` `// Function to find the element` `int` `findEle(` `int` `arr[], ` `int` `n)` `{` ` ` `// sum is use to store` ` ` `// sum of all elements` ` ` `// of array` ` ` `ll sum = 0;` ` ` `for` `(` `int` `i = 0; i < n; i++)` ` ` `sum += arr[i];` ` ` `// iterate over all elements` ` ` `for` `(` `int` `i = 0; i < n; i++)` ` ` `if` `(arr[i] == sum - arr[i])` ` ` `return` `arr[i];` ` ` `return` `-1;` `}` `// Driver code` `int` `main()` `{` ` ` `int` `arr[] = { 1, 2, 3, 6 };` ` ` `int` `n = ` `sizeof` `(arr) / ` `sizeof` `(arr[0]);` ` ` `cout << findEle(arr, n);` ` ` `return` `0;` `}` |

## Java

`// Java implementation of the above approach` `import` `java.io.*;` `class` `GFG {` `// Function to find the element` `static` `int` `findEle(` `int` `arr[], ` `int` `n)` `{` ` ` `// sum is use to store` ` ` `// sum of all elements` ` ` `// of array` ` ` `int` `sum = ` `0` `;` ` ` `for` `(` `int` `i = ` `0` `; i < n; i++)` ` ` `sum += arr[i];` ` ` `// iterate over all elements` ` ` `for` `(` `int` `i = ` `0` `; i < n; i++)` ` ` `if` `(arr[i] == sum - arr[i])` ` ` `return` `arr[i];` ` ` `return` `-` `1` `;` `}` `// Driver code` ` ` `public` `static` `void` `main (String[] args) {` ` ` `int` `arr[] = { ` `1` `, ` `2` `, ` `3` `, ` `6` `};` ` ` `int` `n = arr.length;` ` ` `System.out.print(findEle(arr, n));` ` ` `}` `}` `// This code is contributed by shs..` |

## Python3

`# Python 3 implementation of` `# the above approach` `# Function to find the element` `def` `findEle(arr, n) :` ` ` ` ` `# sum is use to store` ` ` `# sum of all elements` ` ` `# of array` ` ` `sum` `=` `0` ` ` ` ` `for` `i ` `in` `range` `(n) :` ` ` `sum` `+` `=` `arr[i]` ` ` ` ` `# iterate over all elements` ` ` `for` `i ` `in` `range` `(n) :` ` ` `if` `arr[i] ` `=` `=` `sum` `-` `arr[i] :` ` ` `return` `arr[i]` ` ` ` ` `return` `-` `1` `# Driver Code` `if` `__name__ ` `=` `=` `"__main__"` `:` ` ` ` ` `arr ` `=` `[` `1` `, ` `2` `, ` `3` `, ` `6` `]` ` ` `n ` `=` `len` `(arr)` ` ` `print` `(findEle(arr, n))` `# This code is contributed by Ryuga` |

## C#

`// C# implementation of the` `// above approach` `using` `System;` `class` `GFG` `{` `// Function to find the element` `static` `int` `findEle(` `int` `[]arr, ` `int` `n)` `{` ` ` `// sum is use to store` ` ` `// sum of all elements` ` ` `// of array` ` ` `int` `sum = 0;` ` ` `for` `(` `int` `i = 0; i < n; i++)` ` ` `sum += arr[i];` ` ` `// iterate over all elements` ` ` `for` `(` `int` `i = 0; i < n; i++)` ` ` `if` `(arr[i] == sum - arr[i])` ` ` `return` `arr[i];` ` ` `return` `-1;` `}` `// Driver code` `static` `public` `void` `Main (String []args)` `{` ` ` `int` `[]arr = { 1, 2, 3, 6 };` ` ` `int` `n = arr.Length;` ` ` `Console.WriteLine(findEle(arr, n));` `}` `}` `// This code is contributed` `// by Arnab Kundu` |

## PHP

`<?php` `// PHP implementation of the above approach` `// Function to find the element` `function` `findEle(` `$arr` `, ` `$n` `)` `{` ` ` `// sum is use to store` ` ` `// sum of all elements` ` ` `// of array` ` ` `$sum` `= 0;` ` ` `for` `(` `$i` `= 0; ` `$i` `< ` `$n` `; ` `$i` `++)` ` ` `$sum` `+= ` `$arr` `[` `$i` `];` ` ` `// iterate over all elements` ` ` `for` `(` `$i` `= 0; ` `$i` `< ` `$n` `; ` `$i` `++)` ` ` `if` `(` `$arr` `[` `$i` `] == ` `$sum` `- ` `$arr` `[` `$i` `])` ` ` `return` `$arr` `[` `$i` `];` ` ` `return` `-1;` `}` `// Driver code` `$arr` `= ` `array` `(1, 2, 3, 6 );` `$n` `= sizeof(` `$arr` `);` `echo` `findEle(` `$arr` `, ` `$n` `);` `// This code is contributed` `// by Akanksha Rai` `?>` |

## Javascript

`<script>` `// javascript implementation of the above approach` `// Function to find the element` `function` `findEle(arr, n)` `{` ` ` `// sum is use to store` ` ` `// sum of all elements` ` ` `// of array` ` ` `var` `sum = 0;` ` ` `for` `(` `var` `i = 0; i < n; i++)` ` ` `sum += arr[i];` ` ` `// iterate over all elements` ` ` `for` `(` `var` `i = 0; i < n; i++)` ` ` `if` `(arr[i] == sum - arr[i])` ` ` `return` `arr[i];` ` ` `return` `-1;` `}` `// Driver code` ` ` `var` `arr = [1, 2, 3, 6];` ` ` `var` `n = arr.length;` ` ` `document.write(findEle(arr, n));` `// This code is contributed by ipg016107.` `</script>` |

**Output:**

6

**Note:** Above problem can be solved with the concept used in Check if the array has an element which is equal to sum of all the remaining elements.

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