num = [int(x) for x in input()]

for i in range(len(num)-1):
    max_n = max(num[i+1:])
    if num[i]<max_n:
        max_index = num[i+1:].index(max_n)+i+1
        num[max_index] = num[i]
        num[i] = max_n
        break

print("".join(map(str,num)))