#include<bits/stdc++.h>
using namespace std;
int main()
{
  long double R,x,y;
  cin>>R>>x>>y;
  long double d=sqrt((x*x)+(y*y));
  long long ans=1;
  long long s=ceil(d/R);
  if(s==1&&d!=R)
  {
  	ans++;
  }
  else if(s>1)
  {
  	ans=s;
  }
  cout<<ans;
  return 0;
}
#include <iostream>
#include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <fstream>
#include <stack>
#include <vector>
#include <cctype>

typedef long long LL;
typedef unsigned long long uLL;
using namespace std;

const int int_INF = 0x7fffffe0;
const LL LL_INF = 0x7fffffffffffffe0LL;

int main()
{
    LL a[3];
    cin >> a[0] >> a[1] >> a[2];
    sort(a, a + 3);
    if (a[2] - a[1] == a[1] - a[0])
    {
        cout << "Yes";
    }
    else
    {
        cout << "No";
    }
    return 0;
}
