Regular Expression Matching 正则匹配问题

Implement regular expression matching with support for '.' and '*'.

'.' Matches any single character.'*' Matches zero or more of the preceding element.The matching should cover the entire input string (not partial).The function prototype should be:bool isMatch(const char *s, const char *p)Some examples:isMatch("aa","a") → falseisMatch("aa","aa") → trueisMatch("aaa","aa") → falseisMatch("aa", "a*") → trueisMatch("aa", ".*") → trueisMatch("ab", ".*") → trueisMatch("aab", "c*a*b") → true

class Solution {public:    bool isMatch(const char *s, const char *p) {        // Note: The Solution object is instantiated only once and is reused by each test case.            if(p == NULL)            return s!=NULL?false:true;        if(*p == '\0')            return *s == '\0';        if(*(p+1) == '*')        {            while(*s==*p || (*p=='.' && (*s)!='\0') )            {                if(isMatch(s,p+2) )                    return true;                ++s;            }            return isMatch(s,p+2);        }        else        {            if(*s==*p || (*p=='.'&&(*s)!='\0') )                return isMatch(s+1,p+1);            else                return false;        }    }};

参考：

http://blog.csdn.net/hopeztm/article/details/7992253