C++ 算法：计算小于等于n且与7无关的正整数平方和

#include using namespace std;

bool isRelated(int num) { if (num % 7 == 0) { return false; } while (num > 0) { if (num % 10 == 7) { return false; } num /= 10; } return true; }

int main() { int n; cin >> n;

int sum = 0;
for (int i = 1; i <= n; i++) {
    if (isRelated(i)) {
        sum += i * i;
    }
}

cout << sum << endl;

return 0;

}