<p>You are given a positive integer <code>n</code>. Each digit of <code>n</code> has a sign according to the following rules:</p>

<ul>
	<li>The <strong>most significant digit</strong> is assigned a <strong>positive</strong> sign.</li>
	<li>Each other digit has an opposite sign to its adjacent digits.</li>
</ul>

<p>Return <em>the sum of all digits with their corresponding sign</em>.</p>

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

<pre>
<strong>Input:</strong> n = 521
<strong>Output:</strong> 4
<strong>Explanation:</strong> (+5) + (-2) + (+1) = 4.
</pre>

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

<pre>
<strong>Input:</strong> n = 111
<strong>Output:</strong> 1
<strong>Explanation:</strong> (+1) + (-1) + (+1) = 1.
</pre>

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

<pre>
<strong>Input:</strong> n = 886996
<strong>Output:</strong> 0
<strong>Explanation:</strong> (+8) + (-8) + (+6) + (-9) + (+9) + (-6) = 0.
</pre>

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

<ul>
	<li><code>1 &lt;= n &lt;= 10<sup>9</sup></code></li>
</ul>

<p>&nbsp;</p>
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class Solution:
    def alternateDigitSum(self, n: int) -> int:
        digits = []
        while n > 0:
            digits.append(n % 10)
            n = n // 10
        
        res = 0
        k = 0
        for i in range(len(digits)-1, -1, -1):
            digit = digits[i]
            if k % 2 == 0:
                res += digit
            else:
                res += -1 * digit

            k += 1
            
        return res
16