Random whole number between two integers algorithm doesn't work as expected?

JavaScript
1

I’m trying to dissect the random number (between two integers) algorithm provided by MDN and FreeCodeCamp. I do that by simply plugging in numbers and walking through the algorithm step by step on a piece of scratch paper.

Expected result: The random number between a range can go up to, and in fact include the max number.

I’m a bit confused about how to test it, mainly because I feel like I could be doing something wrong given the results.

Actual results: No matter what min/max I choose - my test results appear to demonstrate that the algorithm actually cannot ever result in a random number that goes “near” the max number. The result I always get will never go higher than (max-min). I’m not sure if this is the only issue with this algorithm, but it is the most obvious.

Your code so far


// Example
function ourRandomRange(ourMin, ourMax) {

return Math.floor(Math.random() * (ourMax - ourMin + 1)) + ourMin;
}

ourRandomRange(1, 9);

// Only change code below this line

function randomRange(myMin, myMax) {

return Math.floor(Math.random() * (max - min + 1)) + min;

}

var myRandom = randomRange(5, 15);

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36.

Challenge: Generate Random Whole Numbers within a Range

Link to the challenge:
https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/basic-javascript/generate-random-whole-numbers-within-a-range

2

Your randomRange function will not work because max and min are not defined.

The only way to really see the function randomly generate the maximum value is to run it a large enough number of times.

Here you can see that if I run the example function enough times I will occasionally get the top bound.

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