#include <fstream>
using namespace std;

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

int sir[500001] , aparitii[500000];

int main ()
{
    int lungime_totala , mod , minim , maxim;
    cin >> lungime_totala >> mod >> minim >> maxim;

    long long secvente = 0;
    for (int indice = 1 ; indice <= lungime_totala ; indice++)
    {
        cin >> sir[indice];

        (sir[indice] += sir[indice - 1]) %= mod;
        if (minim <= indice)
            aparitii[sir[indice - minim]]++;

        secvente += aparitii[sir[indice]];
        if (maxim <= indice)
            aparitii[sir[indice - maxim]]--;
    }

    cout << secvente;
    cout.close(); cin.close();
    return 0;
}