#include <iostream>
#include <fstream>
#include <algorithm>
#include <cmath>
#include <cstring>
using namespace std;
ifstream fin("divk.in");
ofstream fout("divk.out");
int v[500001],i,j,a,b,n,k,x,sol;
int main()
{
fin>>n>>k>>a>>b;
for(i=1;i<=n;i++)
{
    fin>>v[i];
    v[i]+=v[i-1];
    v[i]=v[i]%k;
}
for(i=1;i<=n-a+1;i++)
    for(j=i+a-1;j<=i+b-1&&j<=n;j++)
        if((v[j]-v[i-1])%k==0)
            sol++;

fout<<sol;
fin.close();
fout.close();
return 0;
}