import sys
input=sys.stdin.readline

n, k, X, Y = map(int, input().split())
dp = [[-1e9] * k for _ in range(k)]
a = list(map(int, input().split()))

for i in range(n):
    a[i] %= k

X %= k
Y %= k

mx = [-1e9] * k
mx[X] = mx[Y] = 0

dp[X][Y] = 0
dp[Y][X] = 0

for i in range(n):
    x = a[i]
    for j in range(k):
        l = (k - (j + x) % k) % k
        dp[j][l] += 1
        if dp[j][l] > mx[j]:
            mx[j] = dp[j][l]
        if dp[j][l] > mx[l]:
            mx[l] = dp[j][l]
    
    for j in range(k):
        if dp[j][x] < mx[j]:
            dp[j][x] = mx[j]
        if dp[x][j] < mx[j]:
            dp[x][j] = mx[j]
    
    for j in range(k):
        if mx[x] < mx[j]:
            mx[x] = mx[j]

ans = 0
for i in range(k):
    for j in range(k):
        if ans < dp[i][j]:
            ans = dp[i][j]

print(ans)