from sys import stdin
from itertools import repeat

def merge(decks):
    while len(decks)>1:
        left=decks.pop()
        right=decks.pop()
        temp=[]
        while len(left)>0 and len(right)>0:
            if left[0]<right[0]:
                temp.append(left.pop(0))
            else:
                temp.append(right.pop(0))
        temp.extend(left)
        temp.extend(right)
        decks.append(temp)
    temp = []
    for (number,letter) in decks[0]:
        temp.append(letter)
    return "".join(temp)

decks = []
for line in stdin:
    (index, list) = line.split(':')
    deck = zip(map(int, list.split(',')), repeat(index))
    decks.append(deck)
print merge(decks)