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