Baggage Carousel

try:
	while True:
	    #輸入資料
		left_link = input().replace('L:', '').replace('\n', '').replace('\r', '')
		right_link = input().replace('R:', '').replace('\n', '').replace('\r', '')
		location = input().replace('\n', '').replace('\r', '')
		rule = input().replace('\n', '').replace('\r', '')
		
        #利用字典修正重複的連結
		dic_left_link = {}
		dic_right_link = {}
        
        #利用字典的key對應到value，紀錄達到轉盤從輸送帶(key)轉移到下一個輸送帶(value)
		for x in range(len(left_link)-1):
			dic_left_link[left_link[x]] = left_link[x+1]
		for x in range(len(right_link)-1):
			dic_right_link[right_link[x]] = right_link[x+1]

        #直接判斷規則，為R或L，在藉由字典的key連結到下一個輸送帶上
		for x in range(len(rule)):
			if rule[x] == 'L':
				try:
					dic_left_link[location]
				except KeyError:
					pass
				else:
					location = dic_left_link[location]
			if rule[x] == 'R':
				try:
					dic_right_link[location]
				except KeyError:
					pass	
				else:
					location = dic_right_link[location]

		print(location)
except EOFError:
	pass