n = input().strip()
max_num = n
digits = list(n)
length = len(digits)

for i in range(length):
    for j in range(i + 1, length):
        swapped = digits.copy()
        swapped[i], swapped[j] = swapped[j], swapped[i]
        current = ''.join(swapped)
        if current > max_num:
            max_num = current

print(max_num)