Single Number

[kokocan12]

Problem

When an array is given, each element of array is integer.
Every element of array is appear twice, except for one.
Find that one.

Solution

Using bitwise, we can remove repeated one.
ex) 4 ^ 4 = 0, 1 ^ 4 ^ 4 = 1.

The code is below.

const singleNumber = function(nums) {
    let res = 0;
    
    nums.forEach(num => {
        res = num ^ res;
    });
    
    return res;
};