import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

X = read().decode().rstrip()

X = sorted(X, reverse = True)

if X[0] == X[-1]:
    print(-1)
    exit()
if sum(x > '0' for x in X) == 1:
    print(-1)
    exit()    

for i in range(len(X)-2,-1,-1):
    if X[i] == X[i+1]:
        continue
    X[i], X[i+1] = X[i+1], X[i]
    break

answer = ''.join(X)
print(answer)