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First Duplicate - Pure JS

by prakgarnly February 10, 2016

HTML

<ul>
    <li>9</li>
    <li>1</li>
    <li>7</li>
    <li>5</li>
    <li>4</li>
    <li>6</li>
    <li>4</li>
    <li>2</li>
    <li>3</li>
    <li>2</li>
</ul>

JavaScript

/* Find the first duplicate number in the list. it is 4 */

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First Duplicate - Pure JS

HTML

JavaScript

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Join the 4+ million users, and keep the JSFiddle dream alive.

Ad-free

Use pre-released features

Fiddle collections

Private collections and fiddles

Console