Implementation of the regular expression * and? The

A few days ago when using grep, found that grep's * incredibly support problems, and can not get the desired results, so took some time to implement the regular expression x match, the following function can match *,?。

The code is short, but it's efficient.

BOOL Match_star (const char* text,const char* pattern) {const char *CP = text;        Const char* PP = pattern;        const char *PS1, *PS2;        if (!*pattern) return true;                while (*CP) {PS1 = CP;                PS2 = PP;                                while (*ps1 && *ps2) {if (*PS2 = = ' * ') {                                CP = Ps1-1;                                pp = ps2+1;                        Break } else if (0 = = (*PS1-*PS2) | | *ps2 = = '? ')                                {ps1++;                        ps2++;                        } else {break;                }} if (!*PS2) {return true;        } cp++; } return false;} 

Test passes on Windows VC2010 and Linux g++.

When the match X is implemented, a technique is used to compare two new strings and discard what has already been compared.

For example, the string is 1234567890, the pattern string is 1*23*0 and 1? 3 can match the success.

If there is a problem, please correct me, thank you!

Implementation of the regular expression * and? The