#include <iostream>
using namespace std;

int main ()
{
    
    long long a, b, n, d, p, q, r, br = 0;
    
    cin >> a >> b >> n >> d;
    
    for (long long i = a; i <= b; i ++)
    {
        if (i % n == 0)
        {
            p = i;
            r = i / n;
            q = 0;
            while (p > 0)
            {
                q = q * 10 + p % 10;
                p = p / 10;
            }
            
            if (d * r == q)
            {
                br ++;
            }
        }
    }
    
    cout << br << endl;
    return 0;
}
