deffind_first_occurrence(s,char):returns.find(char)# 使用示例my_string="hello world"target_char='o'position=find_first_occurrence(my_string,target_char)print(f"The first occurrence of '{target_char}' is at position{position}") 1. 2. 3. 4. 5. 6. 7. 8. 关系图 接下来,我们使用merma...
Python 中搜索方法的主要问题是它们没有针对速度进行优化。 这会显着减慢您的程序。 The search method in python can be used to find a substring in a given string. This method returns the index of the first occurrence of the substring in the string. If the substring is not found, it returns ...
Thefind()method returns the index of first occurrence of the substring (if found). If not found, it returns-1. Example message ='Python is a fun programming language' # check the index of 'fun'print(message.find('fun')) # Output: 12 Run Code find() Syntax The syntax of thefind()me...
find('AM') Python Copy returns 4 as the first occurrence of “AM” is at 4. rfind The rfind function returns the last occurrence of the substring if found, -1 if not found. s = "MY NAME IS MARK" s.rfind("A") Python Copy returns 12 as the last occurrence of “A” is the ...
Thefind()andindex()methods are used to find the first occurrence of a substring within a string. Both methods return the starting index of the substring if found, and -1 if the substring is not present. However, theindex()method raises aValueErrorexception if the substring is not found. ...
注意#2:find() 方法类似于index()。唯一的区别是 find() 如果没有找到搜索到的字符串,则返回 -1,并且在这种情况下 index() 会抛出异常。 示例1:find() 没有 start 和 end 参数 Python3实现 word='geeks for geeks' # returns first occurrence of Substring ...
There is another method in the string type called find which is more convenient to use than the index(), because there is no need to worry about handling any exceptions. Its function is to return the index of the first occurrence of substring which is found in the string. ...
On each iteration, we use the str.find() method to find the next index of the substring in the string. The str.find method returns the index of the first occurrence of the provided substring in the string. The method returns -1 if the substring is not found in the string. If the su...
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 ...
*block of code* 在描述 Python 语句的形式时,我们使用斜体来标识在程序的某一点可能出现的代码类型。例如,布尔表达式表示任何评估为True或False的表达式可以跟在保留字if后,而代码块表示任何 Python 语句序列可以跟在else:后。 考虑以下程序,如果变量x的值为偶数,则打印“Even”,否则打印“Odd”: ...