#include <iostream>
#include <vector>

using namespace std;

int main()
{
    int n, k, X, Y;
    cin >> n >> k >> X >> Y;
    vector dp(k, vector<int>(k, -1e9));
    vector<int> a(n);
    for (int i = 0; i < n; i++)
    {
        int t;
        cin >> t;
        t %= k;
        a[i] = t;
    }
    X %= k;
    Y %= k;
    vector<int> mx(k, -1e9);
    dp[X][Y] = 0;
    dp[Y][X] = 0;
    mx[X] = mx[Y] = 0;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < k; j++)
        {
            auto l = (k - (j + a[i]) % k) % k;
            dp[j][l]++;
            mx[j] = max(mx[j], dp[j][l]);
            mx[l] = max(mx[l], dp[j][l]);
        }
        for (int j = 0; j < k; j++)
        {
            dp[j][a[i]] = max(dp[j][a[i]], mx[j]);
            dp[a[i]][j] = max(dp[a[i]][j], mx[j]);
        }
        for (int j = 0; j < k; j++) mx[a[i]] = max(mx[a[i]], mx[j]);
    }
    int ans = 0;
    for (int i = 0; i < k; i++) ans = max(ans, mx[i]);
    cout << ans << endl;
}