n = [x for x in input()]

max_num = max(n)
max_num_index = [x for x, i in enumerate(n) if i == max_num].pop()
for x, i in enumerate(n):
    if all(n) == max_num:
        break
    if i != max_num:
        replace_num = i
        replace_index = x
        if replace_index < max_num_index:
            n[max_num_index] = n[replace_index]
            n[replace_index] = max_num
            break
print(int(''.join(n)))