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") → false
isMatch("aa","aa") → true
isMatch("aaa","aa") → false
isMatch("aa","a*") → true
isMatch("aa",".*") → true
isMatch("ab",".*") → true
isMatch("aab","c*a*b") → true
刚开始想错了,没做对,参考网上程序写的:
class Solution { public: bool isMatch(const char *s,const char *p) { if(*p == 0) { return *s == 0; } //不等于'*'的情况 if(*(p + 1) != '*') { //若此时*s和*p相等,则进行isMatch(s+1,p+1)的判断 if(*s && (*s == *p || *p == '.')) { return isMatch(s + 1,p + 1); } return false; } else { for(; *s && (*s == *p || *p == '.'); s++) { //'*' 不再匹配前面的字符. if(isMatch(s,p + 2)) { return true; } //'*'接着匹配前面的字符.继续for循环 } //'*'匹配结束 return isMatch(s,p + 2); } } };