1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
#include <iostream>
using namespace std;

long long f(long long x)
{
    long long result = 0;
    while(x>10)
    {
        int digit = x%10;
        x-=digit;
        digit*=digit;
        result+=digit;
        x/=10;
    }
    x*=x;
    result+=x;
    return result;
}

long long counter(long long k, long long a, long long b)
{
    long long result=0;
    for(long long i = a; i<=b; i++)
    {
        if(k*f(i)==i)
            result++;
    }
    return result;
}

int main()
{
    ios_base::sync_with_stdio(0);
    long long k, a, b;
    cin >> k >> a >> b;
    cout << endl << counter(k, a, b) << endl;
    return 0;
}