#include<iostream>
#include<vector>
#include<bitset>
#include<algorithm>
#include<cmath>
#include<string>
using namespace std;
int main(){ 
    int hour,time,n;
    float num;
    string str,nstr;
    cin >> hour >> time >> str;
    for(int i=4;i<=str.size();i++){
        nstr[i-4] = str[i];
    }
    num = stof(nstr);
    if(str[3]=='-') num*=(-1);
    num*=10;
    n = floor(num);
    n-=90;
    n*=6;
    time+=n;
    while(time<0){
        time+=60;
        hour--;
    }
    while(time>=60){
        time-=60;
        hour++;
    }
    if(hour<0)  hour+=24;
    else if(hour>=24)   hour-=24;

    if(hour<10) cout << '0' << hour;
    else cout << hour;
    cout << ':' ;
    if(time<10) cout << '0' << time << endl;
    else cout << time << endl;
    return 0;
}