#include <fstream>

using namespace std;
ifstream in ("divk.in");
ofstream out ("divk.out");
int nra[100002],nrb[100002],v[500002];
int main()
{
    int k,a,b,i,n,
    in>>n>>k>>a>>b;
    for(i=1;i<=n;i++)
    {
        in>>v[i];
        s=(s+v[i])%k;
        rez+=nra[s]-nrbp[s];
        if(i>=a)
        nra[v[i-a]]++;
        if(i>b)
        nrb[v[i-b-1]]++;
    }
    return 0;
}