#include <bits/stdc++.h>

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

int i,j,k,maxi,mini,n,v[500001],x,l[99999];
long long cnt;

int main()
{
    f>>n>>maxi>>mini>>k;
    for(int i=1;i<=n;i++)
    {
        f>>x;
        v[i]=(v[i-1]+x)%maxi;
        if(i>=mini)l[v[i-mini]]++;
        if(i>k)l[v[i-k-1]]--;
        cnt+=l[v[i]];

    }
    g<<cnt;

}