N = [int(x) for x in input()]

def f():
    global N
    for i in range(len(N)-1):
        s = N[i]
        tmp = max(N[i+1:])
        if tmp>s:
            for j in range(len(N)-1,i,-1):
                if N[j]==tmp:N[i]=N[j];N[j]=s;return
        
f()
print(''.join(map(str,N)))