N = int(input())
A = list(map(int,input().split()))

dp = [[0, 0] for _ in range(N)]
dp[0][0] = 0
dp[0][1] = 1

for i in range(1, N):
    dp[i][0] = max(dp[i - 1])
    if A[i] == A[i - 1]:
        dp[i][1] = max(dp[i - 1]) + 1
    else:
        dp[i][1] = dp[i - 1][0] + 1
        
print(max(dp[-1]))