Backspace String Compare
<p>Given two strings <code>s</code> and <code>t</code>, return <code>true</code> <em>if they are equal when both are typed into empty text editors</em>. <code>&#39;#&#39;</code> means a backspace character.</p>

<p>Note that after backspacing an empty text, the text will continue empty.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;ab#c&quot;, t = &quot;ad#c&quot;
<strong>Output:</strong> true
<strong>Explanation:</strong> Both s and t become &quot;ac&quot;.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;ab##&quot;, t = &quot;c#d#&quot;
<strong>Output:</strong> true
<strong>Explanation:</strong> Both s and t become &quot;&quot;.
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;a#c&quot;, t = &quot;b&quot;
<strong>Output:</strong> false
<strong>Explanation:</strong> s becomes &quot;c&quot; while t becomes &quot;b&quot;.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code><span>1 &lt;= s.length, t.length &lt;= 200</span></code></li>
	<li><span><code>s</code> and <code>t</code> only contain lowercase letters and <code>&#39;#&#39;</code> characters.</span></li>
</ul>

<p>&nbsp;</p>
<p><strong>Follow up:</strong> Can you solve it in <code>O(n)</code> time and <code>O(1)</code> space?</p>
Stack; Two Pointers; String; Simulation
function backspaceCompare(s: string, t: string): boolean {
    let i = s.length - 1;
    let j = t.length - 1;
    while (i >= 0 || j >= 0) {
        let skip = 0;
        while (i >= 0) {
            if (s[i] === '#') {
                skip++;
            } else if (skip !== 0) {
                skip--;
            } else {
                break;
            }
            i--;
        }
        skip = 0;
        while (j >= 0) {
            if (t[j] === '#') {
                skip++;
            } else if (skip !== 0) {
                skip--;
            } else {
                break;
            }
            j--;
        }
        if (s[i] !== t[j]) {
            return false;
        }
        i--;
        j--;
    }
    return true;
}
