HailStoneSequence Solution

What is your hint or solution suggestion?

function hailstoneSequence() {
  var res = [], n =27, c1 = [],  c2 = [351,77031];
/*You already know c2 from Wikipedia page, and its max arr
 length... Please don't make the poor machine do it again... */

  /*While Res Loop Collatz 1*/

  while(n != 1){
   n = (n%2== 0) ? (n/2): (3*n + 1);

  }//End of c1

  var newC1 = [c1[0], c1[1], c1[2], c1[3],
 c1[c1.length-4], c1[c1.length-3], c1[c1.length-2],
 c1[c1.length-1] ];
c1 = newC1;
console.log(`The final c1 matrix before c2 data is ${c1}.\n`);
 console.log(`Final Collatz result matrix is ${res}.\n`);
  return res; 
} /*My 1st Ancient Egyptian Spoiler Tag... Sorry*/

Challenge: Hailstone sequence

Link to the challenge:

Hey @mlpfanatic903!

So I was corrected that for the guide submissions to use the [details][/details] tags.

So that was my bad. Sorry.

You are doing great with these rosetta problems. Keep up the great work. I just finished the 100 doors challenge.

Happy coding!

Thanks… Same to you. I’ve explored the ideas behind the 100 doors challenge, and the map versions seem to run the best for whatever reason…

I have a couple of issues with that solution, it uses old (var) syntax, and it doesn’t really follow the instructions (which suggest to write a helper function to get the hailStone sequence for any given number). This function could then be re-used to calculate the solution for the second task, instead of hardcoding it.

function hailstoneSequence() {
  const res = [];

  /* 1.: Create a routine to generate the hailstone sequence for a number */
  const hailStones = n => {
    let result = [n];
    while (n > 1){
      n = n%2 === 0 ? n/2 : 3*n+1;
    return result;

  /* 2.: Hailstone sequence for n=27 */
  let n = 27;
  const seq1 = hailStones(n);
  const res1 = [...seq1.slice(0,4), ...seq1.slice(-4)];

  /* 3.: Hailstone sequence for n=77031 */
  n = 77031;
  const seq2 = hailStones(n);
  const res2 = [seq2.length, n];
  return res;

So we can agree on the method of implementation, but not on the intrinsic code that does the same function… Interesting Q… To each their own, I guess…
Nice touch with the .slice() method btw.

I just thought that when someone looks up the hints for the second task, and all he finds is a hardcoded array [351,77031], it could be a little disappointing. They may wonder why the challenge includes that second task at all.

Thank you for your guide post contribution. I have taken your suggestions and included the combination in the guide post.

We look forward to your further contribution.

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