## https://yukicoder.me/problems/no/1515

MIN_VALUE = -10 ** 18

def main():
    N, K, X, Y = map(int, input().split())
    A = list(map(int, input().split()))

    dp = [[MIN_VALUE] * K for _ in range(K)]
    dp[X % K][Y % K] = 0
    dp[Y % K][X % K] = 0
    max_dp_x = [0] * K
    for x in range(K):
        m_value = MIN_VALUE
        for y in range(K):
            m_value = max(m_value, dp[x][y])
        max_dp_x[x] = m_value
    max_dp_y = [0] * K
    for y in range(K):
        m_value = MIN_VALUE
        for x in range(K):
            m_value = max(m_value, dp[x][y])
        max_dp_y[y] = m_value

    for a in A:
        a_ = a % K

        updates = {}
        # 結局Aを捨てるもの
        for k_y in range(K):
            k_x_ = (- a_ - k_y) % K
            new_key = (k_x_, k_y) 
            updates[new_key] = dp[k_x_][k_y] + 1
        
        for k_y in range(K):
            k_x_ = (- a_ - k_y) % K
            new_key = (a_, k_y)
            if new_key not in updates:
                updates[new_key] = dp[a_][k_y]
            updates[new_key] = max(updates[new_key], dp[k_x_][k_y] + 1, max_dp_y[k_y])
        
        for k_x in range(K):
            k_y_ = (- a_ - k_x) % K
            new_key = (k_x, a_)
            if new_key not in updates:
                updates[new_key] = dp[k_x][a_]
            updates[new_key] = max(updates[new_key], dp[k_x][k_y_] + 1, max_dp_x[k_x])

        #更新
        for key, value in updates.items():
            x, y = key
            dp[x][y] = max(dp[x][y], value)
            max_dp_x[x] = max(max_dp_x[x], dp[x][y])
            max_dp_y[y] = max(max_dp_y[y], dp[x][y])

    answer = MIN_VALUE
    for x in range(K):
        for y in range(K):
            answer = max(answer, dp[x][y])
    print(answer)



if __name__ == "__main__":
    main()