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"content": "<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>\n\n<ul>\n\t<li>The <strong>most significant digit</strong> is assigned a <strong>positive</strong> sign.</li>\n\t<li>Each other digit has an opposite sign to its adjacent digits.</li>\n</ul>\n\n<p>Return <em>the sum of all digits with their corresponding sign</em>.</p>\n\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 521\n<strong>Output:</strong> 4\n<strong>Explanation:</strong> (+5) + (-2) + (+1) = 4.\n</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 111\n<strong>Output:</strong> 1\n<strong>Explanation:</strong> (+1) + (-1) + (+1) = 1.\n</pre>\n\n<p><strong class=\"example\">Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 886996\n<strong>Output:</strong> 0\n<strong>Explanation:</strong> (+8) + (-8) + (+6) + (-9) + (+9) + (-6) = 0.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= n <= 10<sup>9</sup></code></li>\n</ul>\n\n<p> </p>\n<style type=\"text/css\">.spoilerbutton {display:block; border:dashed; padding: 0px 0px; margin:10px 0px; font-size:150%; font-weight: bold; color:#000000; background-color:cyan; outline:0; \n}\n.spoiler {overflow:hidden;}\n.spoiler > div {-webkit-transition: all 0s ease;-moz-transition: margin 0s ease;-o-transition: all 0s ease;transition: margin 0s ease;}\n.spoilerbutton[value=\"Show Message\"] + .spoiler > div {margin-top:-500%;}\n.spoilerbutton[value=\"Hide Message\"] + .spoiler {padding:5px;}\n</style>\n",
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"The first step is to loop over the digits. We can convert the integer into a string, an array of digits, or just loop over its digits.",
"Keep a variable sign that initially equals 1 and a variable answer that initially equals 0.",
"Each time you loop over a digit i, add sign * i to answer, then multiply sign by -1."
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