#include <iostream>
#include <fstream>

using namespace std;
long v[500001],k,n,a,b,nr;
int main()
{
    ifstream f("divk.in");
    ofstream g("divk.out");

    f>>n>>k>>a>>b;
    for(long i = 1;i<=n;i++)
    {
        f>>v[i];
        v[i]%=k;
        v[i] = v[i-1]+v[i];
    }

    for(long i = 1;i<=n-a;i++)
        for(long j = i+1;j<=i+b && j<=n;j++)
            if((v[j]-v[i])%k == 0)
                nr++;

    g<<nr;

    f.close();
    g.close();

    return 0;
}