如何计算字符串中字符出现的次数?
如。“a”在“Mary had a little lamb”中出现了4次。
如何计算字符串中字符出现的次数?
如。“a”在“Mary had a little lamb”中出现了4次。
当前回答
“不使用计数查找字符串中需要的字符”方法。
import re
def count(s, ch):
pass
def main():
s = raw_input ("Enter strings what you like, for example, 'welcome': ")
ch = raw_input ("Enter you want count characters, but best result to find one character: " )
print ( len (re.findall ( ch, s ) ) )
main()
其他回答
要获得所有字母的计数,请使用集合。计数器:
>>> from collections import Counter
>>> counter = Counter("Mary had a little lamb")
>>> counter['a']
4
你可以使用.count():
>>> 'Mary had a little lamb'.count('a')
4
myString.count('a');
更多信息请点击这里
不超过这个IMHO -你可以添加上或下的方法
def count_letter_in_str(string,letter):
return string.count(letter)
你可以使用循环和字典。
def count_letter(text):
result = {}
for letter in text:
if letter not in result:
result[letter] = 0
result[letter] += 1
return result