Sorting Array with JavaScript reduce function

Question

Often I study some JavaScript interview questions, suddenly I saw a question about usage of reduce function for sorting an Array, I r

Answer 1

You can use an insertion sort:

let array        = [91, 4, 6, 24, 8, 7, 59, 3, 13, 0, 11, 98, 54, 23, 52, 87, 4];
let countIfLess  = (array,v)=> array.reduce((c,n)=>n array.reduce((c,n)=>n==v?c+1:c,0);

console.log(
  array.reduce(
    (a,v,i,array)=>( a[countIfLess(array,v) + countIfEqual(a,v)]=v, a ),
    new Array(array.length)
  )
);

This will create the destination array once and then perform insertions into it at each step of the reduce without having to recreate the destination array.

There are more efficient ways of implementing countIfEqual but I chose to implement all the functions using reduce rather than other array functions.