#include <fstream>
#include <vector>

using namespace std;

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

const int KMAX = 1e5;
vector<int> positions[KMAX + 1];

int CautBinLeft(vector<int> &a, int value)
{
    int st = 0, dr = a.size() - 1, pos = -1;
    while(st <= dr)
    {
        int mij = (st + dr) / 2;
        if(a[mij] >= value)
            pos = mij, dr = mij - 1;
        else
            st = mij + 1;
    }
    return pos;
}

int CautBinRight(vector<int> &a, int value)
{
    int st = 0, dr = a.size() - 1, pos = -1;
    while(st <= dr)
    {
        int mij = (st + dr) / 2;
        if(a[mij] <= value)
            pos = mij, st = mij + 1;
        else
            dr = mij - 1;
    }
    return pos;
}

int main()
{
    int n, k, a, b;
    cin >> n >> k >> a >> b;

    int prefix_rest = 0;
    long long answer = 0;
    for(int i = 1; i <= n; i++)
    {
        int x;
        cin >> x;

        prefix_rest = (prefix_rest + x) % k;

        int left_bound = i - b + 1;
        int right_bound = i - a + 1;

        int pos_left = CautBinLeft(positions[prefix_rest], left_bound);
        int pos_right = CautBinRight(positions[prefix_rest], right_bound);

        if(pos_left != -1)
            answer += pos_right - pos_left + 1;

        positions[prefix_rest].push_back(i);
    }

    cout << answer;


    return 0;
}