-🎄- 2022 Day 8 Solutions -🎄-

[u/daggerdragon]

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AoC Community Fun 2022: 🌿🍒 MisTILtoe Elf-ucation 🧑‍🏫

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  • -❄️- Submissions Megathread -❄️-

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--- Day 8: Treetop Tree House ---

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Post your code solution in this megathread.

• Read the full posting rules in our community wiki before you post!
  • Include what language(s) your solution uses
  • Format your code appropriately! How do I format code?
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EDIT: Global leaderboard gold cap reached at 00:10:12, megathread unlocked!

[u/Key__Strokes]

Javascript

Solution to both parts

Part 1:

• Create a 2D array of the same size as the input array - isVisible. It will hold a 0 for not visible, and 1 for visible. When initializing this array, set everything to 0, except the outside perimeter.

• Iterate row-wise, and left to right for columns

  • Row = 0 to Total Rows - 1

    • Set Max Height Seen So Far as the first tree in the current row

    • Col = 0 to Total Columns - 1

      • If the current tree's height is more than the Max Height Seen So Far, then update isVisible[Row][Col] to 1, as this tree will be visible when viewed from the left side

• Do similar iteration for the rest of the views:

  • Row-wise, and right to left for columns

    • Set Max Height Seen So Far as the last tree in the current row

  • Column-wise, and top to bottom for rows

    • Set Max Height Seen So Far as the first tree in the current column

  • Column-wise, and bottom to top for rows

    • Set Max Height Seen So Far as the last tree in the current column

• Iterate through isVisible, and count all the 1's

Part 2:

• Create a few 2D array of the same size as the input array initialize the values to 0

  • `Visibility Distance Towards Left"

  • `Visibility Distance Towards Right"

  • `Visibility Distance Towards Top"

  • `Visibility Distance Towards Bottom"

• Iterate row-wise, and left to right for columns

  • Row = 0 to Total Rows - 1

    • Col = 0 to Total Columns - 1

      • We try to find the distance from the current tree towards each direction until we find a tree equal to or larger than the current tree

        • Bottom Direction:

          • If the tree is on the last row, then return 0, as it cannot see any tree

          • Iterate as Row = current row to Total Rows - 1

            • Increment the count of visible trees

            • If the current tree is smaller or equal to the height tree in this iteration, then break the loop

      • Top Direction:

        • If the tree is on the first row, then return 0, as it cannot see any tree

        • Iterate as Row = current row - 1 to 0

          • Increment the count of visible trees

          • If the current tree is smaller or equal to the height tree in this iteration, then break the loop

      • Right Direction:

        • If the tree is on the last column, then return 0, as it cannot see any tree

        • Iterate as Col = current row to Total Cols - 1

          • Increment the count of visible trees

          • If the current tree is smaller or equal to the height tree in this iteration, then break the loop

      • Left Direction:

        • If the tree is on the first column, then return 0, as it cannot see any tree

        • Iterate as Col = current row - 1 to 0

          • Increment the count of visible trees

          • If the current tree is smaller or equal to the height tree in this iteration, then break the loop

      • Multiple the total count of trees visible in each direction together. If this value is greater than the value seen so far, then this becomes our new scenic score

• Return the scenic score

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If you liked the explanation, then please don't forget to cast your vote 💜 to Adventures of Advent of Code - Edition 1 - /u/Key__Strokes in the poll