substring：要查找的子字符串。start（可选）：开始查找的起始位置，默认为 0。end（可选）：结束查找的位置，默认为字符串的长度。示例：1. 查找子字符串：text = "Hello, world! This is an example."# 使用 find 查找子字符串index = text.find("world")print("Index of 'world':", index) # 输出...
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...
unt三个函数,分a = 'hello accountant'# Use the upper function to convert the string to uppercasea_upper = a.upper()print(a_upper) # Output: 'HELLO ACCOUNTANT'# Use the find function to find the index of a substring in the stringindex = a.find('accoun')print(index) ...
Index within range 0 to 10:", index_range) # 输出: Index within range 0 to 10: 7 # 查找不存在的子串 nonexistent_substring = "Python" index_not_found = text.find(nonexistent_substring) print("Index of nonexistent substring:", index_not_found) # 输出: Index of nonexistent substring:...
substring = "world" index = text.find(substring) if index != -1: print(f"Substring found at index {index}.") else: print("Substring not found.") 在这个例子中,find() 方法会在 text 字符串中查找 substring,并返回其索引位置。如果找到了子字符串,它会打印出索引位置;如果没有找到,...
If the substring exists inside the string, it returns the index of the first occurence of the substring. If a substring doesn't exist inside the string, it returns-1. Working of find() method Working of Python string's find() and rfind() methods ...
Python String find() 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....
**示例**: ```python main_string = "Hello, world!" substring = "world" index = main_string.find(substring) print("The substring '{}' is found at index {}".format(substring, index)) # 输出: The substring 'world' is found at index 7 ``` ### 在 C++ 中使用 `std::find` C++ ...
python学习string method: find and rfind 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....
2. 使用Python进行反向搜索 在字符串中进行反向搜索 在Python中,字符串可以使用切片和rfind()方法来进行反向搜索。rfind()方法返回最后一次出现指定子字符串的索引。如果找不到该子字符串,返回值为-1。 # 在字符串中反向搜索子字符串 substring = "Python" reverse_index = my_string.rfind(substring) # 输出查...