#include <fstream>

using namespace std;

ifstream f("divk.in");
ofstream g("divk.out");

int n,k,a,b,i,j;
int v[500001];
int rez;

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

    for (i=0;i<n;i++)
        for (j=i+a;j<=i+b && j<=n;j++)
            if (v[i]==v[j])
                rez++;

    g<<rez;

    return 0;
}