ZOJ 3860 Find the Spy

 1 #include <iostream>
 2 #include <cstring>
 3 #include <string>
 4 #include <cstdio>
 5 #include <vector>
 6 #include <cmath>
 7 #include <algorithm>
 8 using namespace std;
 9 int T, N;
10 int a[110];
11 int main(){
12     scanf("%d", &T);
13     while(T--){
14         scanf("%d", &N);
15         int x1, x2;
16         int sum1 = 0, sum2 = 0;
17         for(int i = 1; i <= N; i++){
18             scanf("%d", &a[i]);    
19         }
20         x1 = a[1];
21         sum1 = 1;
22         for(int i = 2; i <= N; i++){
23             if(a[i] != x1){
24                 sum2++;
25                 x2 = a[i];
26             }
27             else sum1++;
28             
29         }
30         if(sum1 == 1) cout<<x1<<endl;
31         else cout<<x2<<endl;
32         
33     }
34     
35    return 0;
36 }