N=input()

L=[]
for i in range(len(N)):
    L.append(N[i])
#print(L)

ans=[L]
import copy
for i in range(len(N)):
    for j in range(i+1,len(N)):
        A=copy.deepcopy(L)
        A[i],A[j]=A[j],A[i]
        ans.append(A)
ans.sort(reverse=True)
print("".join(ans[0]))