# 输入示例
n = int(input().strip())
nums = [0]
nums.extend(list(map(int, input().split())))

# 初始化dp数组
dp = [0 for i in range(n+1)]

for i in range(1,n+1):
    dp[i] = 1    
    for j in range(1,i):
        # dp[i] = 1    !!! 注意，出错了，初始化dp[i]不能放在内循环里，否则在执行内循环时dp[i]会不断初始化为1
        if nums[j]<nums[i]:
            dp[i] = max(dp[i], dp[j]+1)
res = 0
for i in range(n+1):
    res = max(res, dp[i])
print(res)