징검다리

 

import sys

N = int(sys.stdin.readline())
stones = list(map(int, sys.stdin.readline().split()))
mx = [float('-inf')]

dp = [1]*N

for i in range(N):
    for j in range(i + 1, N):
        if stones[i] < stones[j]:
            dp[j] = max(dp[i] + 1, dp[j])

print(max(dp))