剑指Offer 数组中只出现一次的数字

 1 class Solution {
 2 public:
 3     void FindNumsAppearOnce(vector<int> data, int* num1, int *num2) 
 4     {
 5         int res = 0, tag = 0;
 6         if (data.empty())
 7         {
 8             num1 = num2 = 0;
 9         }
10 
11         for (int i = 0; i < data.size(); i++)
12         {
13             res ^= data[i];        
14         }
15 
16         for (; tag < 32; tag++)
17         {
18             if ((res & (1<<tag)) != 0)
19                 break;
20         }
21 
22         for (int i = 0; i < data.size(); i++)
23         {
24             if ((data[i] & (1 << tag)) == 0)
25                 *num1 ^= data[i];
26             else
27                 *num2 ^= data[i];
28         }
29     }
30 };

 1 public static int find1From3(int[] a){
 2         int[] bits = new int[32];
 3         int len = a.length;
 4         for(int i = 0; i < len; i++){
 5             for(int j = 0; j < 32; j++){
 6                 bits[j] = bits[j] + ( (a[i]>>>j) & 1);
 7             }
 8         }
 9         int res = 0;
10         for(int i = 0; i < 32; i++){
11             if(bits[i] % 3 !=0){
12                 res = res | (1 << i);