说明

小B收到了一串数字，其中包含n个数字。

寄件人想知道这<span class="MathJax" id="MathJax-Element-2-fr<x>ame"><span class="math" id="MathJax-Span-4"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-5"><span class="mi" id="MathJax-Span-6" style="font-family:MathJax_Math;font-style:italic;">n</span></span><span></span></span></span><span style="vertical-align:-0.076em;"></span></span></span>个数的异或结果，但小<span class="MathJax" id="MathJax-Element-3-fr<x>ame"><span class="math" id="MathJax-Span-7"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-8"><span class="mi" id="MathJax-Span-9" style="font-family:MathJax_Math;font-style:italic;">B</span></span><span></span></span></span><span style="vertical-align:-0.063em;"></span></span></span>并不会求，就把这个问题转交给你。

但他为了使你求得的更方便，于是运用魔法把这<span class="MathJax" id="MathJax-Element-4-fr<x>ame"><span class="math" id="MathJax-Span-10"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-11"><span class="mi" id="MathJax-Span-12" style="font-family:MathJax_Math;font-style:italic;">n</span></span><span></span></span></span><span style="vertical-align:-0.076em;"></span></span></span>个数都变成了 <span class="MathJax" id="MathJax-Element-5-fr<x>ame"><span class="math" id="MathJax-Span-13"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-14"><span class="mn" id="MathJax-Span-15" style="font-family:MathJax_Main;">1</span></span><span></span></span></span><span style="vertical-align:-0.063em;"></span></span></span>。

现在，你需要求出这 <span class="MathJax" id="MathJax-Element-6-fr<x>ame"><span class="math" id="MathJax-Span-16"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-17"><span class="mi" id="MathJax-Span-18" style="font-family:MathJax_Math;font-style:italic;">n</span></span><span></span></span></span><span style="vertical-align:-0.076em;"></span></span></span>个 <span class="MathJax" id="MathJax-Element-7-fr<x>ame"><span class="math" id="MathJax-Span-19"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-20"><span class="mn" id="MathJax-Span-21" style="font-family:MathJax_Main;">1</span></span><span></span></span></span><span style="vertical-align:-0.063em;"></span></span></span>异或后的结果。关于异或，下表为 <span class="MathJax" id="MathJax-Element-8-fr<x>ame"><span class="math" id="MathJax-Span-22"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-23"><span class="mi" id="MathJax-Span-24" style="font-family:MathJax_Math;font-style:italic;">a</span></span><span></span></span></span><span style="vertical-align:-0.075em;"></span></span></span>与 <span class="MathJax" id="MathJax-Element-9-fr<x>ame"><span class="math" id="MathJax-Span-25"><span style="font-size:125%;"><span><span class="mrow" id="MathJax-Span-26"><span class="mi" id="MathJax-Span-27" style="font-family:MathJax_Math;font-style:italic;">b</span></span><span></span></span></span><span style="vertical-align:-0.076em;"></span></span></span>的异或结果：

输入格式

输入只有一行，该行包含一个整数n  (0≤n≤10¹⁸)。

输出格式

一行一个整数，为答案。

样例

2

0