#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main() {
  int n, l, r;
  cin >> n >> l >> r;
  int ans = 0;
  if (l != r)  {
    for (int i = 0; i <= n / (l + r); i++)  {
      ans += (1 << i);
    }
  }
  else  {
    int i = 0;
    while (n - 2 * i * l > 0)  {
      ans++;
      i++;
    }
  }
  cout << ans;
  return 0;
}