题解 | #火车进站#
火车进站
https://www.nowcoder.com/practice/97ba57c35e9f4749826dc3befaeae109
lst = []
def f(wait,stack,out):
if wait:
f(wait[1:],stack+[wait[0]],out)
if stack:
f(wait,stack[:-1],out+[stack[-1]])
if not wait and not stack:
lst.append(' '.join(map(str,out)))
N = int(input())
ls = list(map(int,input().split()))
f(ls,[],[])
lst.sort()
for i in lst:
print(i)
