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Adrian
Adrian

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What’s your alternative solution? Challenge #46

About this series

This is series of daily JavaScript coding challenges... for both beginners and advanced users.

Each day I’m gone present you a very simple coding challenge, together with the solution. The solution is intentionally written in a didactic way using classic JavaScript syntax in order to be accessible to coders of all levels.

Solutions are designed with increase level of complexity.

Today’s coding challenge

Create a function to calculate the distance between two points defined by their x, y coordinates

(scroll down for solution)

Code newbies

If you are a code newbie, try to work on the solution on your own. After you finish it, or if you need help, please consult the provided solution.

Advanced developers

Please provide alternative solutions in the comments below.

You can solve it using functional concepts or solve it using a different algorithm... or just solve it using the latest ES innovations.

By providing a new solution you can show code newbies different ways to solve the same problem.

Solution

// Solution for challenge41

println(getDistance(100, 100, 400, 300));

function getDistance(x1, y1, x2, y2)
{
    var l1 = x2 - x1;
    var l2 = y2 - y1;

    return Math.sqrt(l1 * l1 + l2 * l2);
}

To quickly verify this solution, copy the code above in this coding editor and press "Run".

Note: The solution was originally designed for codeguppy.com environment, and therefore is making use of println. This is the almost equivalent of console.log in other environments. Please feel free to use your preferred coding playground / environment when implementing your solution.

Top comments (2)

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miketalbot profile image
Mike Talbot ⭐

My first thought is that - hmm, that's as good as it gets. Then as a game programmer I wonder "Why do you want to know?" Because if the question was - given 2 points see if they are less than 40 apart - a much faster solution presents itself. Square roots are very expensive... multiplies not so much.

    function withinRange(x1, y1, x2, y2, range) {
        var dx = x2 - x1
        var dy = y2 - y1
        return (dx * dx + dy * dy) < range * range
    }
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easrng profile image
easrng

Golfed:

let getDistance=(x1, y1, x2, y2, r)=>((x2-x1)**2+(y2-y1)**2) < r**2;