#include <bits/stdc++.h>
// #include <atcoder/all>
#define ll long long
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define repi(i, a, b) for (ll i = (ll)(a); i < (ll)(b); i++)
#define repm(i, a, b) for (ll i = (ll)(a); i > (ll)(b); i--)
#define all(v) v.begin(), v.end()
#define rall(x) (x).rbegin(), (x).rend()
#define pll pair<long long, long long>
#define pb emplace_back
#define mp make_pair
#define mt make_tuple
#define vc vector<char>
#define vvc vector<vc>
using namespace std;
using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<long long>;
using vvll = vector<vll>;
using vb = vector<bool>;
using vvb = vector<vb>;
template <class T>bool chmax(T &a, const T &b){if (a < b){a = b;return 1;}return 0;}
template <class T>bool chmin(T &a, const T &b){if (b < a){a = b;return 1;}return 0;}


int main(){
  ll r,x,y;
  cin>>r>>x>>y;
  ll euc = x*x+y*y;
  ll r2 = r*r;
  if (euc >= r2)cout<<ceil(sqrt(euc/(long double)r2))<<endl;
  else cout<<2<<endl;
}
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define rep(i, n) for(int i=0;i<(int)(n);i++)
#define rep2(i, j, n) for(int i=j;i<(int)(n);i++)
#define all(v) v.begin(), v.end()
using ll = long long;
using P = pair<int, int>;

int main(){
    char a;
    int res1 =0 ,res2 = 0;
    rep(i, 3){
        cin >> a;
        res1 += (int)(a - '0');
    }
    rep(i, 3){
        cin >> a;
        res2 += (int)(a - '0');
    }
    cout << max(res1, res2) << endl;
}
