product_list =[ ('iphone',5800), ('Mac',9800), ('Bike',800), ('iWatch',3800), ('coffee', 30), ('book', 80), ] shopping_list = [] salary = input("Input your salary:") if salary.isdigit():#對整數進行判斷 salary = int(salary) while True: for index,item in enumerate(product_list):#enumerate把列表中下標打出來 #print(product_list.index(item),item) print(index,item) user_choice = input("choose product:") if user_choice.isdigit(): user_choice = int(user_choice) if user_choice < len(product_list) and user_choice >=0: p_item = product_list[user_choice] if p_item[1] <= salary:#買得起 shopping_list.append(p_item) salary -= p_item[1] print("Added %s into shopping cart,your current balance is \033[31;1m%s\033[0m" %(p_item,salary))#出紅色\033[31;1m%s\033[0m else: print("\033[41;1m你的餘額只有[%s]了\033[0m" % salary) else: print("product code [%s] is not exist"% user_choice) elif user_choice =='q': print('------shopping list-------') for p in shopping_list: print(p) print("your current balance:",salary) exit() else: print("invalid option") #break