python之count()函数

# count()统计字符串中特定单词或短语出现次数(n = 3)
strs = \'Good! Today is good day! Good job!\'
n = strs.lower().count("good")
print(strs, "\ngood的个数：", n)
print("输出字符串前五个字符：", strs[0:5])

# 统计列表每个元素中指定单词出现的个数(n = 2)
n = 0
list = [\'good day\', \'bad\', \'well\', \'Good job\']
for i in list:
    n += i.lower().count(\'good\')
print(list, "\ngood的个数：", n)

# 统计列表中指定元素出现的个数(n = 1)
n = 0
n = list.count(\'good day\')
print(list, "\ngood的个数：", n)

　　运行结果：

Good! Today is good day! Good job! 
good的个数： 3
输出字符串前五个字符： Good!
[\'good day\', \'bad\', \'well\', \'Good job\'] 
good的个数： 2
[\'good day\', \'bad\', \'well\', \'Good job\'] 
good的个数： 1