E - Straight Shot -速度合成

E - Straight Shot

 Gym - 101615E 

#include<bits/stdc++.h>
using namespace std;
long long n;
double vx,vy,sum,v,l,r,x;
int main()
{
    while(cin>>n>>x>>vx)
    {
        sum=0;
        while(n--)
        {
            cin>>l>>r>>vy;
            sum+=(r-l)*vy;
        }
        sum=sum/x;
        if(fabs(sum)>vx)
        {
            cout<<"Too hard"<<endl;
            return 0;
        }
        v=sqrt(vx*vx-sum*sum);
        if(v<vx/2)
            cout<<"Too hard"<<endl;
        else
        {
            v=x/v;
            cout<<fixed<<setprecision(3)<<v<<endl;
        }
    }
    return 0;
}