综合练习P2

def solve(n, arr):
    n = int(n)
    arr = list(map(int, str(arr).split(',')))
    lis = [1] * n
    for i in range(1, n):
        for j in range(i):
            if arr[j] < arr[i]:
                lis[i] = max(lis[i], lis[j] + 1)
    lds = [1] * n
    for i in range(n-2, -1, -1):
        for j in range(i+1, n):
            if arr[j] < arr[i]:
                lds[i] = max(lds[i], lds[j] + 1)
    best = max(lis[i] + lds[i] - 1 for i in range(n))
    print(n - best)