python - 如何从列表项更新字典？

Question

我有以下问题:

假设我杀死了一条龙并且它掉落了战利品，我该如何根据战利品更新我的库存？我想出了如果元素栏中不存在战利品如何追加，但如果它们已经存在，我不确定如何更新它。

代码如下:

UserInventory = {'rope': 1, 'torch':6, 'gold coin':42, 'dagger': 1, 'arrow': 12}

def showstuff(storeno):
items_total = 0
for k, v in storeno.items():
    print('Item :' + k + '---' + str(v))
    items_total = items_total + v
print('Total Items:' + str(items_total))

'''def addstuff(inventory, additem):
    I'm not sure what to do here

dragonloot = ['gold coin', 'gold coin', 'rope']
addstuff(UserInventory, dragonloot)'''
showstuff(UserInventory)

Answer 1

你应该看看Counters :

from collections import Counter

inventory = {'rope': 1, 'torch':6, 'gold coin':42, 'dagger': 1, 'arrow': 12}
inventory_ctr = Counter(inventory)

update = ['rope', 'torch']
update_ctr = Counter(update)

new_inventory_ctr = inventory_ctr + update_ctr

print(new_inventory_ctr)