#include <fstream>
using namespace std;
long long a,b,n,d,i,m,j,p,s;
int v[500005];
int main()
{
    ifstream f ("divk.in");
    ofstream g ("divk.out");
f>>n>>d>>a>>b;
for (i=1;i<=n;i++)
    {f>>v[i];}
    for (i=a;i<=b;i++)
    {
        for (j=1;j<=n;j++)
        {
            if (j<a) {s=s+v[j];}
            else if (s%d==0) {
                    p++;
            s=s-v[j-i+1]+v[j];
            }
            else {s=s-v[j-i+1]+v[j];}
    }
}
    g<<p;
}