#include <iostream>
#include <string>
using namespace std;

int main(void){
    char c[10];
    int minI, hourI;
    for(int i=0;i<5;i++){
        cin >> c[i];
    }
    string hour="",min="";
    hour += c[0];
    hour += c[1];
    min += c[3];
    min += c[4];

    hourI = stoi(hour);
    minI = stoi(min);

    minI += 5;

    if(minI >= 60){
        minI -= 60;
        hourI += 1;
    }

    if(hourI >= 24){
        hourI -= 24;
    }
    
    if(hourI < 10){
        cout << "0";
    }
    cout << hourI;
    cout << ":";
    if(minI < 10){
        cout << "0";
    }
    cout << minI << endl;

    return 0;
}