You are asked to implement a simple regex parser which supports two operations: <code>&#39;.&#39;</code> and <code>&#39;*&#39;</code>. The <code>&#39;.&#39;</code> operation matches any single character, while the <code>&#39;*&#39;</code> operation matches zero or more of the preceding element. The matching should cover the entire input string (not partial).

Write a function <code>isMatch(s,p)</code> which takes in two parameters, the string and the regex pattern. It should return a Boolean output indicating a ‘match success’ or a ‘match failure’.

Example 1:

Input:

<pre tabindex="0" class="chroma"><code>s = &#39;aa&#39;
p = &#39;a&#39;
</code></pre>

Output:

<pre tabindex="0" class="chroma"><code>isMatch(s, p) -&gt; False
</code></pre>

Explanation: ‘a’ does not match the entire string ‘aa’.

Example 2:

Input:

<pre tabindex="0" class="chroma"><code>s = &#39;aa&#39;
p = &#39;a*&#39;
</code></pre>

Output:

<pre tabindex="0" class="chroma"><code>isMatch(s, p) -&gt; True
</code></pre>

Explanation: ‘*’ means zero or more of the preceding element, ‘a’. Therefore, by repeating ‘a’ once, it becomes ‘aa’.

Note: There is no need to consider the delimiting of characters ‘.’ and ‘*’

Implement a simple regex parser with operator support for '.' and '*'.

Basic Regex

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