#include <iostream>
#include <fstream>
using namespace std;

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

// rest[i] = (v[1] + ... + v[i]) % K
int v[500001], rest[500001];

int main() {
    int N, K, A, B, i, j, nr = 0;

    fin >> N >> K >> A >> B;

    for (i = 1; i <= N; i++) {
        fin >> v[i];
    }

    for (i = 1; i <= N; i++) {
        rest[i] = (rest[i - 1] + v[i]) % K;
    }

    for (i = A; i <= B; i++) {
        for (j = 1; j <= N - i + 1; j++) {
            if (rest[j + i - 1] == rest[j - 1]) {
                nr++;
            }
        }
    }

    fout << nr;
    return 0;
}