<p>In a string composed of <code>&#39;L&#39;</code>, <code>&#39;R&#39;</code>, and <code>&#39;X&#39;</code> characters, like <code>&quot;RXXLRXRXL&quot;</code>, a move consists of either replacing one occurrence of <code>&quot;XL&quot;</code> with <code>&quot;LX&quot;</code>, or replacing one occurrence of <code>&quot;RX&quot;</code> with <code>&quot;XR&quot;</code>. Given the starting string <code>start</code> and the ending string <code>end</code>, return <code>True</code> if and only if there exists a sequence of moves to transform <code>start</code> to <code>end</code>.</p>

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

<pre>
<strong>Input:</strong> start = &quot;RXXLRXRXL&quot;, end = &quot;XRLXXRRLX&quot;
<strong>Output:</strong> true
<strong>Explanation:</strong> We can transform start to end following these steps:
RXXLRXRXL -&gt;
XRXLRXRXL -&gt;
XRLXRXRXL -&gt;
XRLXXRRXL -&gt;
XRLXXRRLX
</pre>

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

<pre>
<strong>Input:</strong> start = &quot;X&quot;, end = &quot;L&quot;
<strong>Output:</strong> false
</pre>

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

<ul>
	<li><code>1 &lt;= start.length&nbsp;&lt;= 10<sup>4</sup></code></li>
	<li><code>start.length == end.length</code></li>
	<li>Both <code>start</code> and <code>end</code> will only consist of characters in <code>&#39;L&#39;</code>, <code>&#39;R&#39;</code>, and&nbsp;<code>&#39;X&#39;</code>.</li>
</ul>

class Solution:
    def canTransform(self, start: str, end: str) -> bool:
        '''
        swaps={'LX':'XL','RX':'XR'}
        start=list(start)
        for i in range(0,len(start),2):
            print(start)
            if start[i]+start[i+1]==end[i:i+2]:
                continue
            else:
                print(set(start[i:i+2]))
                if set(start[i:i+2])==set(end[i:i+2]):
                    start[i],start[i+1]=start[i+1],start[i]
                else:
                    return False
        print(start)
        return ''.join(start)==end
        '''
        i, j = 0, 0
        n = len(start)
        
        while i < n or j < n:
            while i < n and start[i] == 'X':
                i += 1
            while j < n and end[j] == 'X':
                j += 1
            
            if (i < n) != (j < n):
                return False  # One of them reached the end but the other did not
            
            if i < n and j < n:
                if start[i] != end[j]:
                    return False  # Different characters
                
                if start[i] == 'L' and i < j:
                    return False  # 'L' in start moved to the right
                if start[i] == 'R' and i > j:
                    return False  # 'R' in start moved to the left
            
            i += 1
            j += 1
        
        return True
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