x = int(input())
s = list(str(x))

if len(set(s)) == 1:
    print(-1)
    exit()

s = [int(i) for i in s]
#s.sort(reverse=True)

d = {}
for i in s:
    if i in d:
        d[i] += 1
    else:
        d[i] = 1
#print(d)
keys = list(d.keys())
keys.sort(reverse=True)
ans = []
for k in keys:
    ans += [k]*d[k]
    last = d[k]

ans[-last-1], ans[-last] = ans[-last], ans[-last-1]
if ans[0] == 0:
    print(-1)
else:
    print(''.join(map(str, ans)))