暴力 Codeforces Round #183 (Div. 2) A. Pythagorean Theorem II

题目传送门

 /*
     暴力：O (n^2)
 */
 #include <cstdio>
 #include <algorithm>
 #include <cstring>
 #include <cmath>
 #include <vector>
 using namespace std;

 const int MAXN = 1e4 + ;
 const int INF = 0x3f3f3f3f;

 int main(void)        //Codeforces Round #183 (Div. 2) A. Pythagorean Theorem II
 {
     int n;
     while (scanf ("%d", &n) == )
     {
         int ans = ;
         for (int i=; i<=n; ++i)
         {
             for (int j=i; j<=n; ++j)
             {
                 if (i * i + j * j > n * n)    break;
                 int c = sqrt (i * i + j * j);
                 if (c <= n && c * c == i * i + j * j)    ans++;
             }
         }

         printf ("%d\n", ans);
     }

     return ;
 }