def is_substring(substring, string):if substring in string:return True else:return False main_string = "Hello, World!"sub_string = "World"if is_substring(sub_string, main_string):print("字符串中存在子字符串:", sub_string)else:print("字符串中不存在子字符串:", sub_string)Python3 示例:...
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 this case it’s a conditional that can be eithertrueorfalse.It’ll be true if the substring is part of the ...
range(len(s)):if s[i] notin tmp: tmp += s[i]else: lst.append(tmp) n = tmp.index(s[i]) tmp = tmp[n+1:] + s[i] lst.append(tmp)return max(lst,key=len)str1="babadcda"print(LongestSubstring(str1))问题 8.如何输出给定字符串的全排列#将列表转换为字符串defto...
AI代码解释 str="***this is **string** example...wow!!!***"print(str.strip('*')) 结果: thisis**string** example...wow!!!
fnmatch(string,"*.txt") #win下不区分大小写 fnmatch根据系统决定 fnmatchcase完全区分大小写 timeit(代码执行时间) defisLen(strString): #还是应该使用三元表达式,更快 returnTrueiflen(strString)>6elseFalse defisLen1(strString): #这里注意false和true的位...
Return True if the string is an alpha-numeric string, False otherwise. A string is alpha-numeric if all characters in the string are alpha-numeric and there is at least one character in the string. """ pass 翻译:如果字符串是字母数字的则返回True,否则返回False ...
sub_string="welcome" 1. 步骤3:使用in关键字进行包含性判断 Python中的in关键字可以用来检查一个字符串是否包含另一个字符串。如果包含,它将返回True;如果不包含,它将返回False。 is_contained=sub_stringinmain_string 1. 步骤4:返回布尔值 is_contained变量现在将是一个布尔值,表示子字符串是否在主字符串中...
字符串的下标索引是从0开始的,所以a_string[0:2]会返回原字符串的前两个元素,从a_string[0]开始,直到但不包括a_string[2]。 如果省略了第一个索引值,Python会默认它的值为0。所以a_string[:18]跟a_string[0:18]的效果是一样的,因为从0开始是被Python默认的。 同样地,如果第2个索引值是原字符串的长...
deffind_all_positions(string,substring):positions=[]start=0whileTrue:position=string.find(substring,start)ifposition==-1:breakpositions.append(position)start=position+1returnpositions string="Hello, World! This is a test string."substring="is"positions=find_all_positions(string,substring)print(positio...
| | Raises ValueError when the substring is not found. | | isalnum(...) | S.isalnum() -> bool | | Return True if all characters in S are alphanumeric | and there is at least one character in S, False otherwise. | | isalpha(...) | S.isalpha() -> bool | | Return True if...