#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main(){
    int a;
    cin >> a;
    if((a / 5 * 3) % 60 < 10){
        cout << 10 + (a / 5 * 3) / 60 << ":0" << (a / 5 * 3) % 60 << endl;
    }else{
        cout << 10 + (a / 5 * 3) / 60 << ":" << (a / 5 * 3) % 60 << endl;
    }
}