X = [i for i in input()]

X.sort()

for i in range(len(X) - 1):
    
    if X[i] != X[i + 1]:
        X[i], X[i + 1] = X[i + 1], X[i]
        if X[-1] == '0':
            break
        
        else:
            print(*reversed(X), sep='')
            exit()

print(-1)