# 44. Wildcard Matching

![](/files/ex7q1Jjm09wQnUKC44C5)

![](/files/KTBQLbbGIzyJjIb7ElNB)

```
dp[i][j]: the matching p[0:j] can covert to s[0:i]

in normal thinking: * can be any char or empty so

1.
dp[i][j] = dp[0][j-1] ||  dp[1][j-1] || dp[2][j-1] || ... || dp[i][j-1]

2.
dp[i-1][j] = dp[0][j-1] ||  dp[1][j-1] || dp[2][j-1] || ... || dp[i-1][j-1]

2 replace 1 in part => 
dp[i][j] = dp[i-1][j] || dp[i][j-1]
```

time: O(mn)

space: O(mn)

```java
class Solution {
    public boolean isMatch(String s, String p) {
        int m = s.length();
        int n = p.length();
        boolean[][] dp = new boolean[m+1][n+1];
        
        s = "#" + s;
        p = "#" + p;
        
        dp[0][0] = true;
        
        // dp[1~m][0] => false
        
        // start from [0][1], [0][0] has been initailized
        // when input is "", how pattern can match "", use *, so if no * do break, in the following is all false
        for (int j = 1; j <= n; j++) {
            if (p.charAt(j) != '*') { 
                break;
            }
            dp[0][j] = true;
        }
        
        for (int i = 1; i <= m; i++) {
            for (int j = 1; j <= n; j++) {
                if (p.charAt(j) == '?' || p.charAt(j) == s.charAt(i)) {
                    dp[i][j] = dp[i-1][j-1];
                    
                } else if (p.charAt(j) == '*') {
                    dp[i][j] = dp[i][j-1] || dp[i-1][j];
                }
            }
        }
        return dp[m][n];
    }
}
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://timmybeeflin.gitbook.io/cracking-leetcode/dynamic-programming/pattern-matching-dp/44.-wildcard-matching.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.