#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

constexpr int INF = 1 << 30;

void solve() {
    int n, k;
    cin >> n >> k;

    auto dp = vector(k, vector(k, -INF));
    vector<int> xmax(k, -INF), ymax(k, -INF);

    {
        int x, y;
        cin >> x >> y;
        x %= k, y %= k;

        dp[x][y] = dp[y][x] = 0;

        xmax[x] = xmax[y] = 0;
        ymax[x] = ymax[y] = 0;
    }

    while (n--) {
        int x;
        cin >> x;
        x %= k;

        for (int i = 0; i < k; ++i) {
            // i+j+x=0 mod k
            // j=-(i+x) mod k
            int j = -(i + x) % k;
            if (j < 0) j += k;

            ++dp[i][j];
            xmax[i] = max(xmax[i], dp[i][j]);
            ymax[j] = max(ymax[j], dp[i][j]);
        }

        auto pymax = ymax;
        for (int i = 0; i < k; ++i) {
            dp[i][x] = xmax[i];
            ymax[x] = max(ymax[x], dp[i][x]);
        }

        for (int j = 0; j < k; ++j) {
            dp[x][j] = pymax[j];
            xmax[x] = max(xmax[x], dp[x][j]);
        }
    }

    int ans = -INF;
    for (int i = 0; i < k; ++i) {
        for (int j = 0; j < k; ++j) {
            ans = max(ans, dp[i][j]);
        }
    }
    cout << ans << "\n";
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    solve();

    return 0;
}