import sys
arr = list(map(str, sys.stdin.readline().split()))
n = 1
while n < len(arr):
   for i in range(len(arr) - n):
       if arr[i][1] > arr[i + 1][1]:
           arr[i], arr[i + 1] = arr[i + 1], arr[i]
   n += 1
print(*arr)