forEach method not cooperating- doesn't go to the last index

1

Can someone tell me why my forEach function isn’t including each index of ‘arr’? It only seems to be including [0] and [4] …

function pairwise(arr, arg) {
  let indices = [];
  let sum = 0;
  let holder = [];

 arr.forEach((item)=>{
   let x = arr.indexOf(item)
   for(var i =0; i<arr.length; i++){
      if(item + arr[i] === arg){
        indices.push([x, i]) 
      }
    }
  })

  for(var i=0; i < indices.length; i++){
      if(holder.indexOf(indices[i][0])<0 && holder.indexOf(indices[i][1])<0){
        holder.push(indices[i][0], indices[i][1])
      }
    }

  for(var i =0; i< holder.length; i++){
    sum += holder[i]
  }

  return sum
  }

pairwise([0, 0, 0, 0, 1, 1], 1);
2

I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

See this post to find the backtick on your keyboard. The “preformatted text” tool in the editor (</>) will also add backticks around text.

Note: Backticks are not single quotes.

markdown_Forums

3

  1. forEach has various optional parameters, including the current index. If you use indexOf you just they the index of the first element with that value (arr.indexOf(0) will always return 0 as the first time the number 0 appear in the array is at index 0)

  2. I don’t understand what your code should do. If you want more help you will need to expand on what this algorithm should do.

1 Like
4

Thanks for the feedback!

I figured it out quickly after reading up on forEach parameters. I just needed to utilize the index parameter to make this work correctly!