x = list(input())
l = len(x)
x.sort()
num = x[0]
idx = -1
for i in range(1, l):
    if num == x[i]:
        pass
    else:
        idx = i
        break

if idx == -1:
    print(-1)
    exit()
if l == 2 and x[0] == '0':
    print(-1)
    exit()
#print(x)
x[idx-1], x[idx] = x[idx], x[idx-1]
ans = ''
while l > 0:
    ans += x.pop()
    l -= 1
if ans[0] == '0':
    print(-1)
else:
    print(ans)