def test(number):
    digits = list(number)
    digits.sort()
    digits = ''.join(digits)
    if digits == number:
        return True
    return False


number = input('Enter a number: ')

# print(test(number))

while True:
    if test(number):
        print(f'Output is: {number}')
        break
    else:
        number = str(int(number) - 1)