<p>You are given two strings <code>stamp</code> and <code>target</code>. Initially, there is a string <code>s</code> of length <code>target.length</code> with all <code>s[i] == &#39;?&#39;</code>.</p>

<p>In one turn, you can place <code>stamp</code> over <code>s</code> and replace every letter in the <code>s</code> with the corresponding letter from <code>stamp</code>.</p>

<ul>
	<li>For example, if <code>stamp = &quot;abc&quot;</code> and <code>target = &quot;abcba&quot;</code>, then <code>s</code> is <code>&quot;?????&quot;</code> initially. In one turn you can:

	<ul>
		<li>place <code>stamp</code> at index <code>0</code> of <code>s</code> to obtain <code>&quot;abc??&quot;</code>,</li>
		<li>place <code>stamp</code> at index <code>1</code> of <code>s</code> to obtain <code>&quot;?abc?&quot;</code>, or</li>
		<li>place <code>stamp</code> at index <code>2</code> of <code>s</code> to obtain <code>&quot;??abc&quot;</code>.</li>
	</ul>
	Note that <code>stamp</code> must be fully contained in the boundaries of <code>s</code> in order to stamp (i.e., you cannot place <code>stamp</code> at index <code>3</code> of <code>s</code>).</li>
</ul>

<p>We want to convert <code>s</code> to <code>target</code> using <strong>at most</strong> <code>10 * target.length</code> turns.</p>

<p>Return <em>an array of the index of the left-most letter being stamped at each turn</em>. If we cannot obtain <code>target</code> from <code>s</code> within <code>10 * target.length</code> turns, return an empty array.</p>

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

<pre>
<strong>Input:</strong> stamp = &quot;abc&quot;, target = &quot;ababc&quot;
<strong>Output:</strong> [0,2]
<strong>Explanation:</strong> Initially s = &quot;?????&quot;.
- Place stamp at index 0 to get &quot;abc??&quot;.
- Place stamp at index 2 to get &quot;ababc&quot;.
[1,0,2] would also be accepted as an answer, as well as some other answers.
</pre>

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

<pre>
<strong>Input:</strong> stamp = &quot;abca&quot;, target = &quot;aabcaca&quot;
<strong>Output:</strong> [3,0,1]
<strong>Explanation:</strong> Initially s = &quot;???????&quot;.
- Place stamp at index 3 to get &quot;???abca&quot;.
- Place stamp at index 0 to get &quot;abcabca&quot;.
- Place stamp at index 1 to get &quot;aabcaca&quot;.
</pre>

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

<ul>
	<li><code>1 &lt;= stamp.length &lt;= target.length &lt;= 1000</code></li>
	<li><code>stamp</code> and <code>target</code> consist of lowercase English letters.</li>
</ul>

from typing import List

class Solution:
    def movesToStamp(self, stamp: str, target: str) -> List[int]:
        stamp_len, target_len = len(stamp), len(target)
        
        # Helper function to check if stamp can be placed at index i in target
        def can_stamp(i):
            changed = False
            for j in range(stamp_len):
                if target[i + j] == '?':
                    continue
                if target[i + j] != stamp[j]:
                    return False
                changed = True
            return changed
        
        # Helper function to stamp at index i in target
        def do_stamp(i):
            for j in range(stamp_len):
                if target[i + j] != '?':
                    target[i + j] = '?'
                    nonlocal changes
                    changes += 1
        
        # Initialize target as list for efficient updates
        target = list(target)
        
        # Initialize variables
        result = []
        changes = 0
        max_moves = 10 * target_len
        
        # Loop until target is fully stamped or max moves exceeded
        while changes < target_len:
            found = False
            for i in range(target_len - stamp_len + 1):
                if can_stamp(i):
                    do_stamp(i)
                    result.append(i)
                    found = True
                    if changes == target_len:
                        break
            if not found:
                return []
            if len(result) > max_moves:
                return []
        
        # Reverse the result to get the correct order of moves
        return result[::-1]

# Example usage:
solution = Solution()
print(solution.movesToStamp("abc", "ababc"))  # Output: [0, 2]
print(solution.movesToStamp("abca", "aabcaca"))  # Output: [3, 0, 1]
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