# import sys; input = sys.stdin.buffer.readline
# sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	N = int(input())
	head = ""
	tail = ""
	for i in range(N):
		t, s = list(input().split())
		if t == "0":
			tail += s
		else:
			head += s

	ans = head[::-1] + tail
	print(ans)

if __name__ == '__main__':
	main()