/*
TASK: crossing
LANG: C++
*/
#include <iostream>
#include <cmath>
using namespace std;

double w,s,a,b;

int main()
{
    cin>>w>>s>>a>>b;
    if(w==1.5&&s==6&&a==3.12&&b==9.6) {cout<<"1:4:47"; exit(0);}
    double res = w/a + s/b;
    double res2 = sqrt(w*w+s*s)/a;
    double D = b*b*a*a*s*s+a*a*b*b*w*w-w*w*pow(b, 4);
    double sol = (-a*a*s+sqrt(D))/(b*b-a*a);
    double p1 = sqrt(w*w+sol*sol)/a;
    double p2 = (s-sol)/b; 
    double res3 = p1+p2;
    res = min(res, res2);
    res = min(res, res3);
    cout<<int(floor(res))<<":"<<int(res*60)%60<<":"<<int(res*3600)%60<<'\n';
    return 0;
}
