#include <bits/stdc++.h>
using namespace std;
int main()
{
    char c;
    int h,m;
    cin>>h>>c>>m;
    m+=5;
    if(m>59){
        m-=60;
        h++;
        if(h>23)h=0;
    }
    if(h<10&&m>9)cout<<"0"<<h<<c<<m<<endl;
    if(h>9&&m<10)cout<<h<<c<<"0"<<m<<endl;
    if(h<10&&m<10)cout<<"0"<<h<<c<<"0"<<m<<endl;
    else cout<<h<<c<<m<<endl;
    return 0;
}