#include <fstream>
#define modulo(a) (a>0?a:(-a))

using namespace std;

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

int V[500003];
int N,K,A,B,i,j,t;

int main()
{
    in>>N>>K>>A>>B;
    for(i=1;i<=N;++i)
    {
        in>>t;
        V[i]=V[i-1]+t;
        V[i]-=((V[i]/K)*K);
    }
    t=0;
    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])
            t++;
    }
    out<<t;
    return 0;
}