N = list(input())

for i in range(len(N)):
	m = i
	for j in range(i + 1, len(N)):
		if N[m] <= N[j]:
			m = j	
	if m > i:
		N[m], N[i] = N[i], N[m]
		print("".join(N))
		break
else:
	print("".join(N))