另一种简单直观的方法是使用循环遍历字符串,从末尾开始逐个字符地比较。 # 从后往前查找字符串deffind_last_occurrence(string,substring):n=len(substring)foriinrange(len(string)-n,-1,-1):ifstring[i:i+n]==substring:returnireturn-1 1. 2. 3. 4. 5.
# 使用str.find()查找子字符串的首次出现位置first_occurrence=original_string.find(target_string)print("目标子字符串在原始字符串中的首次出现位置:",first_occurrence) 代码说明: str.find()函数用于查找子字符串在原始字符串中的首次出现位置,如果找到则返回索引值,如果找不到则返回-1。 将first_occurrence变量...
In this last example, we will use the index() method to get the search string in the list:try: my_list.index(search_string) print(True) except ValueError: print(False) # TrueThis example attempts to find the index of search_string within my_list using the index() method. The try ...
import csv def find_last_occurrence(file_path, target_row): last_position = None found = False try: with open('last_position.txt', 'r') as pos_file: last_position = int(pos_file.read()) except FileNotFoundError: pass with open(file_path, 'r') as csvfile: csvreader = csv.read...
str.find(sub[, start[, end]])在字符串中查找sub,找到后返回位置,没找到返回-1. Return the lowest index in the string where substring sub is found, such that sub is contained in the range [start, end]. Optional arguments start and end are interpreted as in slice notation. Return -1 if...
Because of this, the last occurrence of "oo" isn’t counted..find(sub[, start[, end]])You can use .find() to check whether a string contains a particular substring. Calling .find(sub) returns the lowest index in the target string where sub is found:...
Python replace last occurrence of stringIn the next example, we replace the last occurrence of word 'fox'. replace_last.py #!/usr/bin/python msg = "There is a fox in the forest. The fox has red fur." oword = 'fox' nword = 'wolf' n = len(nword) idx = msg.rfind(oword) ...
The first occurrence of str2isat :8The last occurrence of str2isat :21 3. startswith(“string”, beg, end):- 如果字符串是以指定的子字符串开头的,那么返回 True,否则返回 False。 4. endswith(“string”, beg, end):- 如果字符串是以指定的子字符串结尾的,那么返回 True,否则返回 False...
Split the string at the last occurrence of sep, and return a 3-tuple containing the part before the separator, the separator itself, and the part after the separator. If the separator is not found, return a 3-tuple containing two empty strings, followed by the string itself. ...
s.endswith(suffix) # Check if string ends with suffix s.find(t) # First occurrence of t in s s.index(t) # First occurrence of t in s s.isalpha() # Check if characters are alphabetic s.isdigit() # Check if characters are numeric s.islower() # Check if characters are lower-case...