/*
TASK:crossing
LANG:C++
*/
#include <iostream>
using namespace std;
double w,s,a,b,v;
long long  h,m,d;
int main()
{
    cin >> w >> s >> a >> b;
    v=s/b+w/a;
    h=v;
    v=s*60/b+w*60/a;
    m=v-(h*60);
    v=v*60;
    d=v-(m*60+h*3600);
    cout << h << ':' << m << ':'<< d << endl;
    system("PAUSE");
    return 0;
}
     
