mod = 1000000007
eps = 10**-9


def main():
    import sys
    from bisect import bisect_left
    input = sys.stdin.readline

    def solve(A):
        N = len(A)
        LIS = [-10**10]
        L = [0] * N
        for i, a in enumerate(A):
            j = bisect_left(LIS, a)
            if j == len(LIS):
                LIS.append(a)
            else:
                LIS[j] = a
            L[i] = j
        LIS_r = [-10**10]
        R = [0] * N
        A.reverse()
        for i, a in enumerate(A):
            j = bisect_left(LIS_r, a)
            if j == len(LIS_r):
                LIS_r.append(a)
            else:
                LIS_r[j] = a
            R[-1-i] = j
        ret = 0
        for i in range(N):
            ret = max(ret, min(L[i], R[i]) - 1)
        return ret

    N = int(input())
    A = list(map(int, input().split()))
    ans1 = solve(A)
    AA = [-a for a in A]
    ans2 = solve(AA)
    print(max(ans1, ans2))


if __name__ == '__main__':
    main()