#include <bits/stdc++.h> using i64 = long long; using u64 = unsigned long long; using u32 = unsigned; using u128 = unsigned __int128; int main() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); int n; std::cin >> n; std::vector<int> f(n * n); i64 ans = 0; for (int a = 1; a < n; a++) { for (int b = 1; b <= a && a * a + b * b < n * n; b++) { f[a * a + b * b]++; } } for (int l = 1; l <= n; l++) { for (int h = 1; h < l; h++) { ans += f[l * l - h * h]; } } std::cout << ans << "\n"; return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | #include <bits/stdc++.h> using i64 = long long; using u64 = unsigned long long; using u32 = unsigned; using u128 = unsigned __int128; int main() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); int n; std::cin >> n; std::vector<int> f(n * n); i64 ans = 0; for (int a = 1; a < n; a++) { for (int b = 1; b <= a && a * a + b * b < n * n; b++) { f[a * a + b * b]++; } } for (int l = 1; l <= n; l++) { for (int h = 1; h < l; h++) { ans += f[l * l - h * h]; } } std::cout << ans << "\n"; return 0; } |