#include <iostream>
#include <fstream>
using namespace std;
int sir[500005];
long long sume[500005];
int main()
{
    ifstream f("divk.in");
    ofstream g("divk.out");
    int n,k,a,b,i,j;
    long long contor = 0;
    f >> n >> k >> a >>b;
    for (i = 1; i<=n; i++)
    {
        f >> sir[i];
        sume[i] = sume[i-1] + sir[i];
    }
    for (i = 1; i<=n - a; i++)///primul element
    {
        for (j = i; j<=i + b; j++)
        {
            if ((sume[j] - sume[i - 1]) % k == 0)
                contor++;
        }
    }
    g << contor;
    return 0;
}