python编程快速上手之第5章实践项目参考答案

 #!/usr/bin/env python3.5
 # coding:utf-8
 # 5.6.1
 # 好玩游戏的物品清单
 # 给定一个字典，包含物品名称和数量，并打印出数量对应的物品

 dict_stuff = {'rope':1,'torch':6,'gold coin':42,'dagger':1,'arrow':12}
 print("5.6.1参考答案")
 print('=' * 80)
 print("给定字典：",dict_stuff)
 print("运行结果：")
 def displayInventory(inventory):
     print("Inventory:")
     item_total = 0
     for k,v in inventory.items():
         print(str(v) + '\t' + k)
         item_total += v
     print("Total number of items:" + str(item_total))
 displayInventory(dict_stuff)
 print('=' * 80)
 print()

 # 5.6.2
 # 将给定的列表添加到字典中去，并统计相同键对应的数量，最后统计总字典中值的总数
 dragonLoot = ['gold coin','dagger','dagger','gold coin','gold coin','ruby','ruby']

 print("5.6.2参考答案")
 print('=' * 80)
 inv = {'gold coin':42,'rope':1}
 print("给定列表：",dragonLoot)
 print("给定字典：",inv)
 print("运行结果：")

 # 按照SWI的思路,这里可以2种方法：
 # 1是将列表转换成字典再操作
 # 2是用setdefault方法将列表元素加到字典再进行元素个数的自增
 # 在此感谢SWI的指点斧正。

 def addToInventory(inventory,addedItems):
     for item in addedItems:
         inventory.setdefault(item,0)
         inventory[item] += 1
     return inventory
 inv = addToInventory(inv,dragonLoot)
 print(inv)
 displayInventory(inv)
 print('=' * 80)

程序运行结果如下：

(py35env) frank@ThinkPad:py_fas$ python dict_inventory-5.py
5.6.1参考答案
================================================================================
给定字典： {'arrow': 12, 'gold coin': 42, 'dagger': 1, 'rope': 1, 'torch': 6}
运行结果：
Inventory:
12 arrow
42 gold coin
1 dagger
1 rope
6 torch
Total number of items:62
================================================================================

5.6.2参考答案
================================================================================
给定列表： ['gold coin', 'dagger', 'dagger', 'gold coin', 'gold coin', 'ruby', 'ruby']
给定字典： {'rope': 1, 'gold coin': 42}
运行结果：
{'ruby': 2, 'dagger': 2, 'rope': 1, 'gold coin': 45}
Inventory:
2 ruby
2 dagger
1 rope
45 gold coin
Total number of items:50
================================================================================