res = []
def dfs(wait, stack, out):
if not wait and not stack:
res.append(' '.join(map(str, out)))
if wait: # 入栈
dfs(wait[1:], stack + [wait[0]], out)
if stack: # 出栈
dfs(wait, stack[:-1], out + [stack[-1]])
while True:
try:
n, nums = int(input()), list(map(int, input().split()))
dfs(nums, [], [])
for i in sorted(res):
print(i)
except:
break