func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int t;     cin >> t;     while (t--) {       int n, k;       cin >> n >> k;       if (k >= n)         cout << abs(n - k) << endl;       else {         if (n % 2 == 0) {           if (k % 2 == 1)             cout << 1 << endl;           else             cout << 0 << endl;         } else if (n % 2 == 1) {           if (k % 2 == 0)             cout << 1 << endl;           else             cout << 0 << endl;         }       }     }     return 0;   }   