import sys
if sys.platform =='ios':
	import clipboard
	a=clipboard.get()
	a = a.split('\n')
	text = '\n'.join(a)
	with open('input_file.txt','w') as f:
		f.write(text)
	sys.stdin = open('input_file.txt')
sys.setrecursionlimit(4100000)
stdin = sys.stdin 
ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().strip()
nm = lambda: map(int,input().split())

X = list(input())
x = sorted(X)[::-1]
cnt = 0
for i in range(len(X)-1,0,-1):

	if x[i-1] > x[i]:
		x[i-1],x[i] = x[i],x[i-1]
		break
	cnt += 1 


if x[0] == "0":
	print(-1)
	exit()
if cnt == len(X)-1:
	print(-1)
else:
	print("".join(x))