#include <iostream>
#include <fstream>

using namespace std;

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

int v[500005], d[100005];

int main()
{
    int n, k, a, b, x;
    long long s = 0;
    fin >> n >> k >> a >> b;
    for (int i = 1; i <= n; i++)
    {
        fin >> x;
        v[i] = v[i - 1] + x;
    }
    int p = 0, q = 1;
    for (int i = 1; i <= n; i++)
    {
        p++;
        d[v[p] % k]++;
        if (p - q > b - a)
        {
            d[v[q] % k]--;
            q++;
        }
        if (p + a - 1 > n)
            break;
        else
            s += d[v[p + a - 1] % k];
    }
    fout << s << '\n';
    return 0;
}