Learning notes for Python/002-4 (2018-5-20)

tuples and their operations
Tuples are very similar to lists in many places and are ordered, and can be obtained by [] specifying an index, but the tuples cannot be changed after they are created.

names=(‘sheldon‘,‘penny‘,‘leonard‘)print(names)print(names[1])  # 切print(names.count(‘penny‘))  # 统计print(names.index(‘penny‘))  # 索引# names[1]=‘潘妮‘     # 替换  不可以# names.remove(‘penny‘)   # 删  不可以# names.append(‘潘妮‘)   # 增  不可以

Shopping Cart Example
1. Simple Shopping Cart
The shortcomings of the existence of once, the product number is wrong to run the failure;

salary=int(input(‘salary:‘))names1=(‘Iphone‘,‘Bike‘,‘Book‘,‘Car‘)names2=(‘2500‘,‘800‘,‘60‘,‘3000‘)names3=[]print(‘-------------------‘)for i in names1:    num=names1.index(i )    price=names2[names1.index(i) ]    print(num,i,price)print(‘-------------------‘)_abc=input(‘你是否要购物：（add）or（other）‘)while _abc==‘add‘:  num2=int(input("The shopping num:"))  price2=int(names2[num2])  if salary>price2:      names3.append(names1[num2])      names3.append(names2[num2])      print(‘你刚刚购买了：‘,num2,names1[num2],names2[num2 ])      salary=salary-price2      print(‘-------------------‘)      for i in names1:          num = names1.index(i)          price = names2[names1.index(i)]          print(num, i, price)      print(‘-------------------‘)      _abc=input(‘你是否要继续购物：（add）or（other）‘)  else:      print("you money is not enougy")      breakprint("你购买的商品：",names3)print(‘你的余额：‘,salary)

2. After the perfect procedure

product_list=[(' Iphone ', 5800), (' Mac Pro ', 9800), (' Bike ', 8000), (' book ', ' + '), (' Car ', "200"), (' food ')    ] # Nested type shopping_list=[]salary=input (' Input you Salary: ') if Salary.isdigit (): Salary=int (Salary) While True:for Index,item in Enumerate (product_list): # Take out the list of subscript print (Index,item) use_choic  E=input ("What you want to buy:") if Use_choice.isdigit (): Use_choice =int (use_choice) if Use_choice >=0 and Use_choice <len (product_list): p_item=product_list [Use_choice] if p_item[1]<=s Alary:shopping_list. Append (P_item) salary-=p_item[1] Print ("A Dded%s to shopping car,you Moneny is \033[31;1m%s\033[0m "% (P_item, salary)) Else:pri NT ("\033[41;1m your balance is insufficient, only left%s\033[0m"% (Salary)) Else:print ("No such product ...") elif Use_choice = = ' Q ': Print ("----------Shopping list-----------") for I in Shopping_list:print (i) print (' Your balance left%s ' % (Salary)) # Break exit () Else:print ("Invalid option")

Python's Learning note/002-4 (2018-5-20)