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 that will receive two arrays and will return an array with elements that are in the first array but not in the second
(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 challenge26
var ar1 = [1, 2, 3, 10, 5, 3, 14];
var ar2 = [-1, 4, 5, 6, 14];
var ar = mergeLeft(ar1, ar2);
println(ar);
function mergeLeft(ar1, ar2)
{
var ar = [];
for(let el of ar1)
{
if (!ar2.includes(el))
{
ar.push(el);
}
}
return ar;
}
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 ofconsole.log
in other environments. Please feel free to use your preferred coding playground / environment when implementing your solution.
Top comments (2)
So, here is my plain JavaScript solution:
To clearly show the intent of such operations I created my own little library flooent.
If it was an array of objects and we are comparing the field
key
: