Only one occurrence of the number

Given An array of numbers nums , in which exactly-elements appear only once and all the other elements appear exactly Twice. Find the elements that appear only once.

For example:

Given nums = [1, 2, 1, 3, 2, 5] , return[3, 5]

classSolution { Public: Vector<int> Singlenumber (vector<int>&nums) {    intX_xor_y =0;  for(intn:nums) {x_xor_y^=N; }    //find the last one 1//1 indicates that the value of this point two is different, one is 1 is 1, otherwise it cannot be different or appear 1    intMask = x_xor_y & ~ (X_xor_y-1); intx =0; inty =0; //X:xor of A,a,b,b,x//Y:xor of C,c,y     for(intn:nums) {        if(N &mask) {x^=N; } Else{y^=N; }    }    returnvector<int>{x, y};}};

Given an array of integers, every element appears twice except for one. Find the single one.

class Solution {public:    int singlenumber (intint  N) {         int0;      for 0; I < n; + +i)        {^= a[i]    ;    } return num;    }};

Given an array of integers, every element appears three times except for one. Find the single one.

int singlenumber (vector<int> AA) {    int00;     // int size = sizeof (AA)/sizeof (int);     for (int0; i < aa.size (); i++) {        = (ones ^ aa[i]) & ~twos;         = (twos ^ aa[i]) & ~ones;    }     return ones;}

Only one occurrence of the number