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### by Sumit Chourasia | Apr 19, 2020 | Category :coding | Tags : आसानडेटा-संरचनाleetcodealgorithm

#### Find a single occurring element in an array where each element occurred twice. - मिनी टीवी

Given a non-empty array of integers, every element appears twice except for one. Find that single one.

Note:

Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?

Example 1:

Input: [2,2,1]

Output: 1

Example 2:

Input: [4,1,2,1,2]

Output: 4

Solution:

``````using System;
using System.Collections.Generic;
using System.Text;

namespace LeetCode.Easy
{
class SingleNumberSolution
{
public void execute()
{

var input = new int[] { 2, 2, 1 };
int res = SingleNumber(input);
}

public int SingleNumber(int[] nums)
{
int val = nums[0];
for (int i = 1; i < nums.Length; i++)
{
val = val ^ nums[i];
}
return val;
}
}
}
``````

Time Complexity: O(n)

Space Complexity: O(1)

Contributed By: Sumit Chourasia
Contributed By: Sumit Chourasia
Contributed By: Sumit Chourasia
Contributed By: Sumit Chourasia