Wildcard Matching

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).

Example

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: Sequence DP.

public boolean isMatch(String s, String p) {
    if(s.length() == 0 && p.length() == 0) {
        return true;
    }
    int m = s.length(), n = p.length();
    boolean[][] dp = new boolean[m + 1][n + 1];
    dp[0][0] = true;
    for(int i = 1; i <= m; i++) {
        if(dp[i - 1][0] && s.charAt(i - 1) == '*') {
            dp[i][0] = true;
        }
        else {
            dp[i][0] = false; 
        }
    }
    for(int i = 1; i <= n; i++) {
        if(dp[0][i - 1] && p.charAt(i - 1) == '*') {
            dp[0][i] = true;
        }
        else {
            dp[0][i] = false;
        }
    }
    for(int i = 1; i <= m; i++) {
        for(int j = 1; j <= n; j++) {
            if(s.charAt(i - 1) == p.charAt(j - 1) || s.charAt(i - 1) == '?' ||
               p.charAt(j - 1) == '?') {
                dp[i][j] = dp[i - 1][j - 1];
            }
            if(s.charAt(i - 1) == '*' || p.charAt(j - 1) == '*') {
                dp[i][j] = dp[i - 1][j] || dp[i][j - 1];
            }
        }
    }
    return dp[m][n];
}