#include <bits/stdc++.h>
using namespace std;
int main() {
  long long a, b, k, a1, b1;
  cin >> k >> a >> b;
  long long left = (a >= 0 ? k * ((a + k - 1) / k) : k * (a / k));
  long long right = (b >= 0 ? k * (b / k) : k * ((b - k + 1) / k));
  if (left > right) {
    cout << 0 << endl;
  } else if (left == right) {
    cout << 1 << endl;
  } else {
    cout << (right - left) / k + 1 << endl;
  }
  return 0;
}
