import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]

def main():
    ok = set()
    ng = set()
    name_to_i = {}
    n = int(input())
    for i in range(n):
        ng_name, ok_name = input().split()
        ok.add(ok_name)
        ng.add(ng_name)
        if ng_name not in name_to_i:
            name_to_i[ng_name] = i * 2
        if ok_name not in name_to_i:
            name_to_i[ok_name] = i * 2 + 1
    ok -= ng
    for name in sorted(ok, key=lambda x: name_to_i[x]):
        print(name)

main()