#include <bits/stdc++.h>   using namespace std;   int main() {     int s1, s2, t1, t2;     char ch1, ch2;     cin >> s1 >> ch1 >> s2;     cin >> t1 >> ch2 >> t2;     int a = s1 - t1;     int b = s2 - t2;     if (b < 0) {       b += 60;       a--;     }     if (a < 0) {       a += 24;     }     cout << right << setw(2) << setfill( 0 ) << a <<  : ;     cout << right << setw(2) << setfill( 0 ) << b << endl;     return 0;   }   