COVID

try:
	while True:
		#輸入每筆資料
		remaining_task = input()
		remaining_task = remaining_task.replace('\r', '')
		remaining_task = remaining_task.replace('\n', '')
		remaining_task = int(remaining_task)
		ID_number = input()
		task_list = input()

		#允許的天數
		allow_date = 0		
		if int(ID_number[-1])%2 == 1:
			allow_date = 1	#因為Python的for迴圈起始為0，所以奇數天為0, 2, 4...，偶數天為1, 3, 5...

		#開始判斷口罩剩餘量
		for x in range(len(task_list)):
			#沒口罩(remaining_task == 0)或禮拜日(x == 6, 13, 20...)的情況下，迴圈不做事
			if remaining_task == 0 or x%7 == 6:
				continue
			#判斷當天要做的事情，也就是判斷task code
			else:
				if task_list[x] == 'A':
					continue
				elif task_list[x] == 'B':
					remaining_task -= 1
				elif task_list[x] == 'C':
					remaining_task -= 2
				elif task_list[x] == 'D':
					if x%2 == allow_date:
						remaining_task += 2
					else:
						remaining_task -= 1
				elif task_list[x] == 'E':
					if x%2 == allow_date:
						remaining_task += 4
					else:
						remaining_task -= 1
				elif task_list[x] == 'F':
					if x%2 == allow_date:
						remaining_task += 5
					else:
						continue
				else:
					if x%2 == allow_date:
						remaining_task += 10
					else:
						continue
		#印出結果
		print(remaining_task)
#最後兩行為判斷如果輸入行為空白則停止程式
except EOFError:
	pass