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#include <iostream>
using namespace std;

namespace {
  constexpr auto max_s = 9*9*18;

  int sqr(int x)
  {
    return x*x;
  }

  int f(long long n)
  {
    int res = 0;
    while (n > 0) {
      res += sqr(n % 10);
      n /= 10;
    }
    return res;
  }

  int solve(long long k, long long a, long long b)
  {
    int res = 0;

    for (long long s = (a+k-1) / k; s <= max_s && s <= b/k; ++s) {
      if (f(k*s) == s) ++res;
    }

    return res;
  }
}

int main()
{
  iostream::sync_with_stdio(false);
  cin.tie(NULL);

  long long k, a, b;
  cin >> k >> a >> b;
  cout << solve(k, a, b) << '\n';

  return 0;
}