#include <iostream>
#include<utility>
#include <vector>
#include <map>
#include<string>
#include<queue>
#include<math.h>
#define pb push_back
#define all(x) begin(x),end(x)
#define ll long long
#define P pair<int,int>
#define lP pait<ll,ll>
using namespace std;
int main() {
    int a,b;
    char e;
    cin>>a>>e>>b;
    if(a<9){
        if(b>54){
            cout<<'0'<<a+1<<e<<'0'<<(b+5)%60<<endl;
    }
        else cout<<'0'<<a<<e<<b+5<<endl;
    }
    else if(a==23){
        if(b>54){
        cout<<'0'<<(a+1)%24<<e<<'0'<<(b+5)%60<<endl;
    }
        else cout<<a<<e<<b+5<<endl;
    }
    else {
        if(b>54){
        cout<<(a+1)%24<<e<<'0'<<(b+5)%60<<endl;
    }
        else cout<<a<<e<<b+5<<endl;
    }
    
    return 0;
}