Hamming Distance(随机算法)

http://acm.hdu.edu.cn/showproblem.php?pid=4712

题意：计算任意两个十六进制的数异或后1的最少个数。

思路：用随机数随机产生两个数作为下标，记录这两个数异或后1的个数，输出1的个数最少是多少。

 #include <stdio.h>
 #include <algorithm>
 #include <time.h>
 #include <math.h>

 using namespace std;
 const int N=;
 const int INF=<<;
 int f[N];
 int main()
 {
     int t;
     scanf("%d",&t);
     while(t--)
     {
         int n,ans = INF;
         scanf("%d",&n);
         for (int i = ; i < n; i ++)
             scanf("%x",&f[i]);
         srand((unsigned)time(NULL));
         for (int i = ; i < N*; i ++)
         {
             int a = rand()%n;
             int b = rand()%n;
             if (a==b)
                 continue ;
             int t = f[a]^f[b];
             int temp = __builtin_popcount(t);
             ans = min(ans,temp);
         }
         printf("%d\n",ans);
     }
     return ;
 }