<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> </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> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= n <= 10<sup>9</sup></code></li> </ul> <p> </p> <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; } .spoiler {overflow:hidden;} .spoiler > div {-webkit-transition: all 0s ease;-moz-transition: margin 0s ease;-o-transition: all 0s ease;transition: margin 0s ease;} .spoilerbutton[value="Show Message"] + .spoiler > div {margin-top:-500%;} .spoilerbutton[value="Hide Message"] + .spoiler {padding:5px;} </style>