czj/VS Code/g.cpp

//我是个傻逼
#include <iostream>
//我是个傻逼
#include <math.h>
using namespace std;
int main(){
    double h,v,t;
    cin>>h;
    t=sqrt(h/4.9);
    v=9.8*t;
    cout<<v;
    system("pause");
    return 0;
}