CS Learning - Generate large array of natural numbers

by Hari Menon

HTML

<span>Size: </span>
<input type="text" name="size" id="size"> <span>Max: </span>
<input type="text" name="size" id="maximum">
<button id="calculate">Calculate</button>
<br><pre id="output"></pre>

JavaScript

function setOutput(output) {
    document.querySelector('#output').innerHTML = output;
}

function generateLargeUniqueArray(size, max) {
    var array = [];
    while (array.length < size) {
        var randomNumber = Math.ceil(Math.random() * max);
        if (array.indexOf(randomNumber) == -1) {
            array.push(randomNumber);
        }
    }
    return array;
}

document.querySelector('#calculate').onclick = function () {
    var size = document.querySelector('#size').value;
    var max = document.querySelector('#maximum').value;
    var array = generateLargeUniqueArray(size, max);
    setOutput(JSON.stringify(array, null, 2));
};