How to count duplicate value in an array in javascript

Question

Currently, I got an array like that:

var uniqueCount = Array();

After a few steps, my array looks like that:

uniqueCount =          


        

Answer 1

Simple is better, one variable, one function :)

const counts = arr.reduce((acc, value) => ({
   ...acc,
   [value]: (acc[value] || 0) + 1
}), {});