deffind_substrings(string,substrings):positions=[]forsubstringinsubstrings:index=string.find(substring)positions.append(index)returnpositions# 示例用法string="This is a test string."substrings=["is","test","string"]positions=find_substrings(string,substrings)print(positions)# 输出:[2, 10, 17] ...
下面是将以上四个步骤整合在一起的完整代码示例: defindex_of_substring(string,substring):string_list=list(string)forindex,charinenumerate(string_list):ifchar==substring[0]:# 判断当前字符是否与子字符串的第一个字符相同ifstring[index:index+len(substring)]==substring:# 判断当前字符后续字符是否与子字符...
Note that find() function returns the index position of the substring if it’s found, otherwise it returns -1. Count of Substring Occurrence We can usecount() functionto find the number of occurrences of a substring in the string. s = 'My Name is Pankaj' print('Substring count =', s...
Write a Python program to determine the index of a given string at which a certain substring starts. If the substring is not found in the given string return 'Not found'. Sample Solution: Python Code: # Function to find index of substring def find_Index(str1, pos): # Check if pos lo...
# find the index of isresult = text.index('is') print(result)# Output: 7 index() Syntax It's syntax is: str.index(sub[, start[, end]] ) index() Parameters Theindex()method takes three parameters: sub- substring to be searched in the stringstr. ...
The index method can’t return a number because the substring isn’t there, so we get a value error instead: In order to avoid thisTraceback Error, we can use the keywordinto check if a substring is contained in a string. In the case of Loops, it was used for iteration, whereas in...
The find() method returns the lowest index of the substring if it is found in given string. If its is not found then it returns -1. Syntax : str.find(sub,start,end) Parameters : sub :It’s the substring which needs to be searched in the given string. ...
python 自带的两个查找字符串的方法:find 和rfind. Python String find() Method Description: This method determines ifstroccurs in string, or in a substring of string if starting indexbegand ending indexendare given. beg 和 end 可以缺省,这样find整个字符串 ...
If tabsize is not given, a tab size of 8 characters is assumed. """ return "" def find(self, sub, start=None, end=None): """ 寻找子序列位置,如果没找到,返回 -1 """ """ S.find(sub [,start [,end]]) -> int Return the lowest index in S where substring sub is found, such...
sub- It is the substring to be searched in thestrstring. startandend(optional) - The rangestr[start:end]within which substring is searched. find() Return Value Thefind()method returns an integer value: If the substring exists inside the string, it returns the index of the first occurence ...