/*

x和y值和题目相反，搞了了好几遍

*/

#include<bits/stdc++.h>

#define exp 1e-9

#define pi acos(-1)

using namespace std;

/*

小车不靠墙壁段的直线方程

*/

double dis(double Q,double l,double d,double x)

{

    double b=d/cos(Q)+l*sin(Q);

    return (b-x)/tan(Q);

}

int main()

{

    //freopen("C:\\Users\\acer\\Desktop\\in.txt","r",stdin);

    double x,y,l,d;

    while(scanf("%lf%lf%lf%lf",&x,&y,&l,&d)!=EOF)

    {

        double left=,right=pi/,mid,midmid;

        //cout<<right<<endl;

        while(right-left>exp)

        {

            mid=left+(right-left)/;

            midmid=right-(right-left)/;

            //假设求解最大极值.

            if(dis(mid,l,d,x)>=dis(midmid,l,d,x))

                right=midmid;

            else

                left=mid;

        }

        //cout<<"mid="<<mid<<endl;

        //cout<<(int)dis(mid,l,d,x)<<endl;

        if(dis(mid,l,d,x)<y)

            puts("yes");

        else

            puts("no");

    }

    return ;

}