#include <bits/stdc++.h>
using namespace std;
int main() {
  long long k, a, b;
  cin >> k >> a >> b;
  long long c, d;
  if (a < 0)
    c = a * -1;
  else
    c = a;
  d = c;
  d %= k;
  if (d != 0) {
    if (a < 0) {
      a -= (k - d);
      a += k;
    } else
      a += (k - d);
  }
  long long ans;
  if (a <= b)
    ans = (b - a + k) / k;
  else
    ans = 0;
  cout << ans << endl;
}
