Rob Pike wrote 30 lines of codes to realize a simple regular expression matcher in his book The practice of Programming. This piece of code is really cool. Let's take a look at the code.Meaning of different characters.CharacterMeaningcGeneral character.Match any single character^Match start of a string$Match end of a string*Match zero or many occurrences of a character/*match ：Test the regexp in text*/int match(char* regexp,char* text){    if(regexp[0] == '^')        return matchhere(regexp+1,text);     do{ /*Check the strin...