#include <iostream>
#include <cstdio>
#include <cstdlib>
using namespace std;

int main(){
    int hour,minites;
    string utc;
    cin >> hour >> minites >> utc;
    utc = utc.substr(3,utc.length()-1);
    auto dot = utc.find(".");
    string sign = utc.substr(0,1);
    string utc_h = utc.substr(1,dot-1);
    string utc_m = ((dot!=-1)?(utc.substr(dot+1,utc.length()-1)):"0");
    
    int intsign = (sign=="+")?1:-1;
    
    int hour_diff = intsign*atoi(utc_h.c_str())-9;
    int minites_diff = intsign*atoi(utc_m.c_str())*6;
    
    hour += hour_diff;
    minites += minites_diff;
    
    if (hour_diff>0){
        if (minites>=60) hour++,minites%=60;
        hour%=24;
    }
    else{
        if (minites<0) hour--,minites+=60;
        if (hour<0) hour+=24;
    }
    printf("%02d:%02d",hour,minites);
    return 0;
}