44. Wildcard Matching

Description

Given an input string (s) and a pattern (p), implement wildcard pattern matching with support for '?' and '*' where:

• '?' Matches any single character.
• '*' Matches any sequence of characters (including the empty sequence).

The matching should cover the entire input string (not partial).

 

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'.

 

Constraints:

• 0 <= s.length, p.length <= 2000
• s contains only lowercase English letters.
• p contains only lowercase English letters, '?' or '*'.

 

Solutions

Solution: Dynamic Programming

• Time complexity: O(mn)
• Space complexity: O(mn)

 

JavaScript

/**
 * @param {string} s
 * @param {string} p
 * @return {boolean}
 */
const isMatch = function (s, p) {
  const n = s.length;
  const m = p.length;
  const dp = new Array(n + 1)
    .fill('')
    .map(_ => new Array(m + 1).fill(false));

  dp[0][0] = true;

  for (let index = 0; index < m; index++) {
    if (p[index] !== '*') continue;
    dp[0][index + 1] = dp[0][index];
  }
  for (let a = 1; a <= n; a++) {
    for (let b = 1; b <= m; b++) {
      const str = s[a - 1];
      const pattern = p[b - 1];

      if (pattern === '*') {
        dp[a][b] = dp[a - 1][b] || dp[a][b - 1];
        continue;
      }
      if (str !== pattern && pattern !== '?') continue;
      dp[a][b] = dp[a - 1][b - 1];
    }
  }
  return dp[n][m];
};