import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]

def swap_int(s,i,j):
    aa=list(s)
    aa[i],aa[j]=aa[j],aa[i]
    t="".join(aa)
    return int(t)

def main():
    s=input()
    ans=[int(s)]
    for i in range(len(s)):
        for j in range(i):
            ans.append(swap_int(s,i,j))
    print(max(ans))

main()