44. Wildcard Matching
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Given an input string (s) and a pattern (p), implement wildcard pattern matching with support for '?' and '*'.

'?' Matches any single character.
'*' Matches any sequence of characters (including the empty sequence).
The matching should cover the entire input string (not partial).

Note:

s could be empty and contains only lowercase letters a-z.
p could be empty and contains only lowercase letters a-z, and characters like ? or *.
Example 1:

Input:
s = "aa"
p = "a"
Output: false
Explanation: "a" does not match the entire string "aa".
Example 2:

Input:
s = "aa"
p = "*"
Output: true
Explanation: '*' matches any sequence.
Example 3:

Input:
s = "cb"
p = "?a"
Output: false
Explanation: '?' matches 'c', but the second letter is 'a', which does not match 'b'.
Example 4:

Input:
s = "adceb"
p = "*a*b"
Output: true
Explanation: The first '*' matches the empty sequence, while the second '*' matches the substring "dce".
Example 5:

Input:
s = "acdcb"
p = "a*c?b"
Output: false
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Difficulty:Hard
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Total Submissions:638.5K
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Related Topics 
StringDynamic ProgrammingBacktrackingGreedy
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Java	





comparison
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class Solution {
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   boolean isMatch(String str, String pattern) {
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        int s = 0, p = 0, match = 0, starIdx = -1;            
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        while (s < str.length()){
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            // advancing both pointers
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            if (p < pattern.length()  && (pattern.charAt(p) == '?' || str.charAt(s) == pattern.charAt(p))){
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                s++;
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                p++;
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            }
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            // * found, only advancing pattern pointer
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            else if (p < pattern.length() && pattern.charAt(p) == '*'){
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                starIdx = p;
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                match = s;
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                p++;
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            }
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           // last pattern pointer was *, advancing string pointer
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            else if (starIdx != -1){
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                p = starIdx + 1;
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                match++;
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                s = match;
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            }
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           //current pattern pointer is not star, last patter pointer was not *
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          //characters do not match
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            else return false;
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        }
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        //check for remaining characters in pattern
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        while (p < pattern.length() && pattern.charAt(p) == '*')
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            p++;
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        return p == pattern.length();
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}
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}