def mergeMaxValue(lst):
    m = len(max(lst, key=len))
    newLst = [(i,i+i[-1]*(m-len(i))) for i in lst]
    newLst.sort(key=lambda item:item[1], reverse=True)
    result = "".join(item[0] for item in newLst)
    print(result)

lst = list(map(str, input().split(',')))
mergeMaxValue(lst)