dictionaries are like bags - no order
purse =
dict()
purse[
'money']=
12purse[
'candy']=
3purse[
'tissues']=
75print
(purse)
# print
(purse[
'candy'])
# 3purse[
'candy'
]= purse[
'candy']+
2print
(purse)
#
if name in counts:
x = counts[name]
else
: x =
0
//如果counts中存在name的key,那麼返回它的value,否則返回0
x = counts.get(name,
0)
counts =
dict()
names =
['csev'
,'cwen'
,'csev'
,'zqian'
,'cwen'
]for name in names :
counts[name]
= counts.get(name,0)
+1# if name not in counts :
# counts[name] = 1
# else :
# counts[name] = counts[name] + 1
print
(counts)
#
counts =
dict()
line =
input
('enter a line of text:'
)words = line.split(
)#預設以space為分隔符
print
('words:'
, words)
print
('counting...'
)for word in words:
counts[word]
= counts.get(word,0)
+1print
('counts'
, counts)
counts =
for key in counts:
print
(key, counts[key]
)#for迴圈裡同時有兩個變數
#for aaa, bbb in counts.items() :
# print(aaa, bbb)
# chuck 1
# fred 42
# jan 100
jjj =
print
(list
(jjj)
)# ['jan', 'chuck', 'fred']
print
(jjj.keys())
# ['jan', 'chuck', 'fred']
print
(jjj.values())
# [100, 1, 42]
print
(jjj.items())
# [('jan', 100), ('chuck', 1), ('fred', 42)]
統計txt檔案中最長出現的word並說出出現的次數
name =
input
('enter file:'
)handle =
open
(name)
#統計共有幾種word，以及它們出現的次數
counts =
dict()
for line in handle:
words = line.split(
)for word in words:
counts[word]
= counts.get(word,0)
+1#統計最長出現的word以及它的次數
bigcount =
none
bigword =
none
for word, count in counts.items():
#注意.items()不要漏掉哦！
if bigcount is
none
or count > bigcount:
bigword = word
bigcount = count
#輸出print
(bigword, bigcount)
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