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

int n,k,a,b;
int v[500006];
long long s[500006],cn;

void citire(){
ci>>n>>k>>a>>b;
for(int i=1;i<=n;i++){
    ci>>v[i];
}

}

void creare_s(){
int i;
for(i=1;i<=n;i++){
    s[i]=v[i]+s[i-1];

}

}

void rez(){
int nr,i,j;
for(i=1;i<=n-a+1;i++){
    for(j=i+a-1;j<=i+b-1;j++){
            if(j<=n){
        //cout<<i<<" "<<j<<"\n";
        if((s[j]-s[i-1] )%k==0 ){
            cn++;
        }
    }
    }
}

cou<<cn;

}
///2 9 5 4 1 4
int main()
{
    citire();
    creare_s();
    rez();
    return 0;
}