[热身题][hdoj_2095]find your present (2)

// hdoj_2095 find your present (2)// 562MS220K230 BGCC#include <stdio.h>int main(void){int i, n, x, s;while(scanf("%d", &n), n){s = 0;for(i = 0; i < n; i ++){scanf("%d", &x);s ^= x;}printf("%d\n", s);}return 0;}

while(scanf("%d", &n), n) 用到了逗号表达式

s ^= x; 用到了异或运算

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1^1 = 0

1^0 = 1

0^1 = 1

0^0 = 0