HDU 2095 find your present (2)

find your present (2)

Time Limit: 1000/2000 MS (Java/Others)Memory Limit: 32768/1024 K (Java/Others)
Total Submission(s): 6852Accepted Submission(s): 2509

#include <iostream>using namespace std;int main(){ int n, a, pre; while (scanf("%d", &n), n) { pre = 0; while (n--) { scanf("%d", &a); pre ^= a; } printf("%d\n", pre); } return 0;}
代码系够短，不过^运算其实系好费时间噶。