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#include <iostream>
using namespace std;
int kwadrat(long long n){
    int s=0, b;
    while( n>0){
         b=n%10;
         n/=10;
         s+=b*b;
    }
    return s;
}

int main() {
    long long k,a,b,s,ctr=0;
    cin>>k>>a>>b;
    if(a%k==0){
        s=a/k;
    }else{
        s=a/k+1;
    }
    while(s<=b/k && s<=81*18){
       int n=s*k;
       if(kwadrat(n)==s)
        ctr++;
       s++;
    }
    cout<<ctr;
    return 0;
}