from decimal import *
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 main():
    s=input()
    t=list(s)
    mx=max(t)
    idx=s.rfind(mx)
    if idx>0:t[0],t[idx]=t[idx],t[0]
    print("".join(t))

main()