Python - 在字典中添加值

Question

这是我的代码：

inv = {'rope': 1, 'torch': 6, 'gold coin': 42, 'dagger': 1}

def display_inventory(inventory):
    #inv = {'rope': 1, 'torch': 6, 'gold coin': 42, 'dagger': 1}
    print("Inventory:")
    for key, value in inv.items():
            print value, key
    print("")
    print "Number of items is: ",
    print (sum(inv.values())),

def add_to_inventory(inventory, added_items):
    dragon_loot_dict = dict.fromkeys(added_items, 1)
    #print(dragon_loot_dict)
    inventory=dict(inventory.items()+ dragon_loot_dict.items())
    print(inventory)


dragon_loot = ['gold coin', ' dagger', 'gold coin', 'gold coin', 'ruby']

add_to_inventory(inv, dragon_loot)

我刚开始学习 Python。 当我将怪物的战利品添加到我的主库存时，主库存中的值正在更改为怪物库存中的值。

如何添加相同物品的价值，例如gold coin ？

Answer 1

您可以遍历dragon_loot_dict的项目并将值添加到inventory的相应键。 使用dict.setdefault初始化键，以防inventory还没有这样的键。

改变：

inventory=dict(inventory.items()+ dragon_loot_dict.items())

到：

for k, v in dragon_loot_dict.items():
     inventory[k] = inventory.setdefault(k, int) + v

Answer 2

您可以迭代战利品并增加库存中的密钥

inv = {'rope': 1, 'torch': 6, 'gold coin': 42, 'dagger': 1}
dragon_loot = ['gold coin', ' dagger', 'gold coin', 'gold coin', 'ruby']

def add_to_inventory(inventory, items):
    for item in items:
         # get count of item in inventory, or 0 if item is not in inventory
         item_count = inventory.get(item, 0)
         # update item count in inventory
         inventory[item] = item_count + 1
    print(inventory)

add_to_inventory(inv, dragon_loot)

结果：

#inv = {'rope': 1, 'torch': 6, 'gold coin': 45, 'dagger': 2, 'ruby':1}