func_code_string: #include <bits/stdc++.h>   using namespace std;   long long arr[10000001];   int main() {     long long d = 1;     arr[0] = 0;     for (int i = 1; i < 10000001; i++) {       arr[i] = arr[i - 1] + d;       d += 2;     }     int t;     cin >> t;     for (int i = 0; i < t; i++) {       int n, k;       cin >> n >> k;       if (n % 2 == 0 && k % 2 != 0) {         cout <<  NO  << endl;         continue;       }       if (n % 2 != 0 && k % 2 == 0) {         cout <<  NO  << endl;         continue;       }       long long x = arr[k];       if (n >= x)         cout <<  YES  << endl;       else         cout <<  NO  << endl;     }     return 0;   }   