c语言代码,实现在一字符串中查询子字符串,如果找到,返回子字符串位置WritethefollowingfunctioninC.stripos—Findpositionoffirstoccurrenceofacase-insensitivestringintstripos(char*haystack,char*needle,intoffset)Returnsthenumericpositionofthefirstoccurrenceofneedleinthehaystackstring.Notethattheneedlemaybeastringofone