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#include <iostream>
using namespace std;

long long int f(long long int n){
    long long int x, p;
    x=p=0;
    while(n){
        p=n%10;
        x+=p*p;
        n/=10;
    }
    return x;
}

int main()
{
    long long int k, a, b;
    cin >> k >> a >> b;
    int ile=0;
    if(a%k) a=a-(a%k)+k;
    if(k*1800<b) b=k*1800;
    for(long long int n=a; n<=b; n+=k)
        if(k*f(n)==n)ile++;
    cout << ile;
   return 0;
}