기억하기
이차원 visited 만들기
get((), 1) 사용
def recur(cur):
global ans
if cur == r:
ans = max(ans, int("".join(num)))
return
for i in range(len(num)-1):
for j in range(i+1, len(num)):
num[i], num[j] = num[j], num[i]
a = "".join(num)
if visited.get((a, cur), 1):
visited[(a, cur)] = 0
recur(cur + 1)
num[i], num[j] = num[j], num[i]
num, r = input().split()
num, r = list(num), int(r)
visited = {}
ans = -1
if len(num) == 1 or (len(num) == 2 and '0' in num):
pass
else:
recur(0)
print(ans)
/