Wildcard Matching

Desicription

Implement wildcard pattern matching with support for '?' and '*'.

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'?' Matches any single character.
'*' Matches any sequence of characters (including the empty sequence).
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", "*") → true
isMatch("aa", "a*") → true
isMatch("ab", "?*") → true
isMatch("aab", "c*a*b") → false

Solution

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class Solution {
public:
bool isMatch(string s, string p) {
int s_len = s.size();
int p_len = p.size();
int s_index = 0;
int p_index = 0;
int s_back_index = -1;
int p_back_index = -1;
for(s_index = 0, p_index = 0; s_index < s_len; s_index++, p_index++){
if(p[p_index] == '*'){
s_back_index = s_index;
p_back_index = p_index;
s_index--;
}
else{
if(s[s_index] != p[p_index] && p[p_index] != '?'){
if(s_back_index >= 0){
s_index = s_back_index++;
p_index = p_back_index;
}
else
return 0;
}
}
}
while(p[p_index] == '*')
p_index++;
return p_index == p_len;
}
};