#include<bits/stdc++.h>
using namespace std;
using ll=long long;
#define rep(i,p,n)for(ll i=(ll)p;i<(ll)n;i++)
#define all(x)(x).begin(),(x).end()
#define edt(x1,y1,x2,y2)sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2))

int main() {
    string T;
    cin>>T;
    ll hh=stoll(T.substr(0,2));
    ll mm=stoll(T.substr(3,2));
    mm+=5;
    if(mm>=60){
        mm-=60;
        hh++;
    }
    if(hh>=24){
        hh-=24;
    }
    cout<<setfill('0')<<right<<setw(2)<<hh<<":"<<setw(2)<<mm<<endl;
    return 0;
}