#include <bits/stdc++.h>
using namespace std;
ifstream in("divk.in");
ofstream out("divk.out");


int v[500001],n,a,b,k,c[500001];

int main()
{
in >> n >> k >> a >> b;
for ( int i =1 ; i <=n ; ++i)in>>v[i];
for ( int i =1 ; i<= n ; ++ i )
{    c[i]=(c[i-1]+v[i])%k;
}
int nr = 0 ;
for ( int i =0 ; i<= n ; ++ i )
{
    int elem = c[i];
    for (int j = i+a;j<=i+b&&j<=n;++j)
        if(elem==c[j]) ++nr;}
    out << nr ;

    return 0;

}