#include <iostream>
#include <fstream>
using namespace std;

ifstream fin("divk.in");
ofstream fout("divk.out");

int n, k, a, b, length, sum;
int v[500010], S[500010], L[500010];

int main()
{
    fin >> n >> k >> a >> b;

    for(int i=1;i<=n;i++)
    {
        fin >> v[i];
        S[i]=v[i]+S[i-1];
    }

    for(int i=a;i<=n;i++)
        for(int j=i-b+1;j<=i-a+1;j++)
            if((S[i]-S[j-1])%k==0)
               ++L[i];

    for(int i=1;i<=n;i++)
        sum+=L[i];

    fout << sum;
    return 0;
}