def sort(values):
	for i in range(len(values)):		
		for j in range(i, len(values)):			
			if (values[i] > values[j]):
				temp = values[i]
				values[i] = values[j]
				values[j] = temp
 k = raw_input().rstrip()
kList = list(k)
sortkList)
print("".join(kList))

39a9f87e7f3f9006fbde83df8bdf6f64ff6edcb5
def sort(values):
	for i in range(len(values)):		
		for j in range(i, len(values)):			
			if (values[i] > values[j]):
				temp = values[i]
				values[i] = values[j]
				values[j] = temp
 k = raw_input().rstrip()
kList = list(k)
sortkList)
print("".join(kList))
