#include <iostream>
#include <algorithm>
#include <string>
using namespace std;
 
int main(void){
    
    string s;
    cin >> s;
    
    int h = (s[0]-'0')*10+(s[1]-'0');
    int m = (s[3]-'0')*10+(s[4]-'0');
    
    m += 5;
    
    if(m >= 60){
        m -= 60;
        
        h+=1;
        
        h %= 24;
        
    }
    
    printf("%02d:%02d\n",h,m);
    
}