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#include <iostream>

using namespace std;

int main()
{
    ios_base::sync_with_stdio;
    unsigned long long int a, b, k, sum, n, licz, licz2;

    cin >> k >> a >> b;
   if(a % k != 0)
    a = a - a%k + k;
    licz = 0;
    for(;a <= b; a = a+k )
    {
        n = a, sum = 0, licz2 = 0;
        while(n > 0)
        {
            sum = sum + (n%10)*(n%10);
            n = n/10;
            licz2++;
        }

    if(k*sum == a) licz++;
    if(licz2*81*k<a) break;

    }
  cout << licz;
}