这个代码哪里不对啊小白求助谢谢

#include<bits/stdc++.h>
using namespace std;
const double PI = 3.14;
int main()
{
    int h, r,v,n;
    cin >> h >> r;
    v = r * r * PI * h;
    n = (20000 / v)+1;
    cout << n;
    return 0;
}