字典

Sss123057057

书上的
allguess={'1':{'apples':5,'pretzeles':12},
         '2':{'ham sandwiches':3,'apples':2},
         '3':{'cups':3,'apple pies':1}}
def a(guests,item):
    numbrount=0
    for k,v in guests.items():
        numbrount=numbrount+v.get(item,0)
    return numbrount
print('number of things being brought:')
print('  apples '+str(a(allguess, 'apples')))
print('  cups '+str(a(allguess, 'cups')))
print('  cakes '+str(a(allguess, 'cakes')))
print('  ham sandwich '+str(a(allguess, 'ham sandwiches')))
print('  apple pies '+str(a(allguess, 'apple pies')))
        可是没有用到k，我改成了这样
allguess={'1':{'apples':5,'pretzeles':12},
         '2':{'ham sandwiches':3,'apples':2},
         '3':{'cups':3,'apple pies':1}}
def a(guests,item):
    numbrount=0
    for v in guests.values():
        numbrount=numbrount+v.get(item,0)
    return numbrount
print('number of things being brought:')
print('  apples '+str(a(allguess, 'apples')))
print('  cups '+str(a(allguess, 'cups')))
print('  cakes '+str(a(allguess, 'cakes')))
print('  ham sandwich '+str(a(allguess, 'ham sandwiches')))
print('  apple pies '+str(a(allguess, 'apple pies')))
有什么弊端吗？

kogawananari

没有

_2_

那除了这样，难道还有别的更加简便的把字典的键和值单独提取出来的方法吗？