#include <cstdio>
using namespace std;
long long s[500005];
int v[500005];
int main()
{
    freopen ("divk.in", "r", stdin);
    freopen ("divk.out", "w", stdout);
    int n, k, a, b, i, j;
    scanf ("%d%d%d%d", &n, &k, &a, &b);
    for (i = 1; i <= n; i ++)
    {
        scanf ("%d", &v[i]);
        s[i] = s[i - 1] + 1LL * v[i];
    }
    int p, u = 0;
    for (p = a; p <= b; p ++)
    {
        for (i = 1; i <= n - p + 1; i ++)
            if ((s[i + p - 1] - s[i]) % k == 0)
            u ++;
    }
    printf ("%d\n", u);
    return 0;
}