#37 - Row of the odd triangle - CodeWars Kata (6 kyu)

Instructions

Given a triangle of consecutive odd numbers:

               1
            3     5
         7     9    11
      13    15    17    19 
   21    23    25    27    29

find the triangle's row knowing its index (the rows are 1-indexed), e.g.:

odd_row(1) == [1]
odd_row(2) == [3, 5]
odd_row(3) == [7, 9, 11]

Note: your code should be optimized to handle big inputs.

My solution:

function oddRow(n) {
  let first = 1;
  for(let i = 1; i<n; i++){
    first+=i*2
  }

  let r = [first];
  for(let i = 1; i<n; i++){
    r.push(first+=2)
  }

  return r
}

Explanation

First I got the first value of the row that I'm searching on, I did this by using a for loop that will iterate the number of rows, and in every iteration I changed the value of the var "first" by adding 2 to it and revaluing it.

  for(let i = 1; i<n; i++){
    first+=i*2
  }

After that with that value I made the variable "r" that will contain the result that will be returned, inside of it I stored the first number of the row

let r = [first];

After that I used another loop and inside of it, I pushed every value after the first plus 2, and at the end I just returned "r"

for(let i = 1; i<n; i++){
    r.push(first+=2)
  }

  return r

What do you think about this solution? 👇🤔

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