N, K, x, y = map(int, input().split())
A = list(map(lambda x: int(x) % K, input().split()))
x %= K
y %= K

# dp[i,j]: 手持ちがi,j -> 最大スコア
inf = 10**5
inf = 10
dp = [[-inf] * K for _ in range(K)]
memo = [-inf] * K
dp[x][y] = 0
dp[y][x] = 0
memo[x] = 0
memo[y] = 0

for a in A:
    for x in range(K):
        y = (K - x - a) % K
        if dp[x][y] >= 0:
            dp[x][y] += 1
            memo[x] = max(memo[x], dp[x][y])
    for x in range(K):
        if memo[x] < 0:
            continue
        dp[x][a] = max(dp[x][a], memo[x])
        dp[a][x] = max(dp[x][a], memo[x])
    memo[a] = max(dp[a])

ans = 0
for i in range(K):
    for j in range(K):
        ans = max(ans, dp[i][j])
print(ans)