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#include <iostream>
#include <cmath>
using namespace std;

int digit_square(int x){
	int n = ceil(log10(x));
	int d,dd;
	int result = 0;
	
	for (int i=1; i<=n; i++){
		dd = int(pow(10,i));
		d =10*(x%dd)/dd;
		x = x - d*dd/10;
		
		result+=d*d;
		}
	return result;	
	}

int main() {
	int k, a, b;
	int count = 0;
	cin>>k>>a>>b;
	
	a = a - a % k + k;
	b = b - b % k;
	
	for(int i = a; i<=b; i+=k){
		if( digit_square(i) == i/k){
			count++;}
		}
	cout<<count;

	return 0;
}