题解 | #搬圆桌#简单的公式计算

#include<iostream>
#include<cmath>
using namespace std;
int main()
{
    int r, x, y, x1, y1;
    while(cin >> r >> x >> y >> x1 >> y1)
    {
        double dist = sqrt(pow(x-x1,2)+pow(y-y1,2));
        cout << (int)dist/r/2 << endl;
    }
}