from fractions import gcd
from heapq import*
import math
from collections import defaultdict, Counter
import sys
sys.setrecursionlimit(10 ** 7)
MOD = 10 ** 9 + 7


def main():
    n = int(input())
    sn = list(str(n))
    base = int(sn[0])
    change = -1
    for i in range(1, len(sn)):
        if int(sn[i]) > base:
            change = i

    sn[0], sn[change] = sn[change], sn[0]
    print(max(n, int("".join(map(str, sn)))))


if __name__ == '__main__':
    main()