<p>You are given a string <code>s</code> and two integers <code>x</code> and <code>y</code>. You can perform two types of operations any number of times.</p>

<ul>
	<li>Remove substring <code>&quot;ab&quot;</code> and gain <code>x</code> points.

	<ul>
		<li>For example, when removing <code>&quot;ab&quot;</code> from <code>&quot;c<u>ab</u>xbae&quot;</code> it becomes <code>&quot;cxbae&quot;</code>.</li>
	</ul>
	</li>
	<li>Remove substring <code>&quot;ba&quot;</code> and gain <code>y</code> points.
	<ul>
		<li>For example, when removing <code>&quot;ba&quot;</code> from <code>&quot;cabx<u>ba</u>e&quot;</code> it becomes <code>&quot;cabxe&quot;</code>.</li>
	</ul>
	</li>
</ul>

<p>Return <em>the maximum points you can gain after applying the above operations on</em> <code>s</code>.</p>

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

<pre>
<strong>Input:</strong> s = &quot;cdbcbbaaabab&quot;, x = 4, y = 5
<strong>Output:</strong> 19
<strong>Explanation:</strong>
- Remove the &quot;ba&quot; underlined in &quot;cdbcbbaaa<u>ba</u>b&quot;. Now, s = &quot;cdbcbbaaab&quot; and 5 points are added to the score.
- Remove the &quot;ab&quot; underlined in &quot;cdbcbbaa<u>ab</u>&quot;. Now, s = &quot;cdbcbbaa&quot; and 4 points are added to the score.
- Remove the &quot;ba&quot; underlined in &quot;cdbcb<u>ba</u>a&quot;. Now, s = &quot;cdbcba&quot; and 5 points are added to the score.
- Remove the &quot;ba&quot; underlined in &quot;cdbc<u>ba</u>&quot;. Now, s = &quot;cdbc&quot; and 5 points are added to the score.
Total score = 5 + 4 + 5 + 5 = 19.</pre>

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

<pre>
<strong>Input:</strong> s = &quot;aabbaaxybbaabb&quot;, x = 5, y = 4
<strong>Output:</strong> 20
</pre>

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

<ul>
	<li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li>
	<li><code>1 &lt;= x, y &lt;= 10<sup>4</sup></code></li>
	<li><code>s</code> consists of lowercase English letters.</li>
</ul>

# class Solution:
#     def maximumGain(self, s: str, x: int, y: int) -> int:
        
#         fp, sp, fc, sc = ('ab', 'ba', x, y) if x > y else ('ba', 'ab', y, x)

#         print(fp)
#         print(sp)

#         sl = list(s)

#         remove = True
#         r = sl
#         count = 0
#         while(remove):
#             result = []
#             i = 0
#             remove = False
#             while i < len(r)-1:
#                 if r[i] == fp[0] and r[i+1] == fp[1]:
#                     count += fc
#                     i += 2
#                     remove = True
#                 elif r[i] == sp[0] and r[i+1] == sp[1]:
#                     count += sc
#                     i += 2
#                     remove = True
#                 else:
#                     result.append(r[i])
#                     i += 1
                    
#             r = result
#             print(r, count)

#         return count

class Solution:

    def remove_group(self, sl: List[str], group: str, score: int) -> (List[str], int):

        stack = []
        count = 0
        for s in sl:
            if len(stack) == 0:
                stack.append(s)
            elif stack[-1] == group[0] and s == group[1]:
                stack.pop()
                count += score
            else:
                stack.append(s)
        return stack, count



    def maximumGain(self, s: str, x: int, y: int) -> int:
        
        fp, sp, fc, sc = ('ab', 'ba', x, y) if x > y else ('ba', 'ab', y, x)

        print(fp)
        print(sp)

        sl = list(s)

        s,score = self.remove_group(sl, fp, fc)
        print(s, score)

        s,score2 = self.remove_group(s, sp, sc)
        print(s, score2)
        
        return score + score2
412