51Nod 1087 1 10 100 1000

 1 #include<iostream>
 2 #include<algorithm>
 3 #include<cmath>
 4 using namespace std;
 5 
 6 int main()
 7 {
 8     std::ios::sync_with_stdio(false);
 9     int t, n;
10     cin >> t;
11     while (t--){
12         cin >> n;
13         if (n == 1){ cout << "1" << endl; continue; }
14         int k = sqrt(2 * (n - 1));//判断2*n=k*(k+1)
15         for (int i = k;; i++){
16             if (i*(i + 1) == 2 * (n - 1)){
17                 cout << "1" << endl;
18                 break;
19             }
20             if (i*(i + 1) > 2 * (n - 1)){
21                 cout << "0" << endl;
22                 break;
23             }
24         }
25 
26     }
27     return 0;
28 }