#include <iostream>
#include <fstream>
#define nmax 500001

using namespace std;

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

int n,k,a,b,i,x,j,num=0;
long s[nmax];

int main(){
    
    in >> n >> k >> a >> b;
    
    for (i=1; i<=n; i++)
        in >> s[i], s[i]=(s[i-1]+s[i])%k;
    
    for (i=1; i<=n; i++)
        for (j=i+a-1; j<=i+b-1; j++){
            if (j>n) break;
            if ((s[j]-s[i-1])%k==0) num++;
        }
    
    out << num << "\n";
    
    return 0;
}