func_code_string: #include <bits/stdc++.h>   using namespace std;   long long n, k;   void solve() {     cin >> n >> k;     if (n < k) {       cout << k - n <<   n ;       return;     }     if ((n % 2 == 0 and k % 2 == 0) or (n % 2 == 1 and k % 2 == 1))       cout << 0 <<   n ;     else       cout << 1 <<   n ;   }   signed main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     long long t;     cin >> t;     for (long long i = 1; i <= t; i++) solve();   }   