#include <iostream>
#include <fstream>

using namespace std;

int a, i, s[500100], j, b, n, k, v[500100];
long long r;

int main()
{
	ifstream f("divk.in");
	ofstream g("divk.out");

	f >> n >> k >> a >> b;
	for (i = 1; i <= n; i++)
	{
		f >> v[i];
		s[i] = s[i - 1] + v[i];
	}
	for (i = 1; i <= n; i++)
	{
		for (j = i + a; j <= i + b; j++)
		{
			if ((s[j] - s[i - 1]) % k == 0)
				r++;
			else
				break;
		}
	}
	g << r;
	return 0;
}