diff --git a/README.md b/README.md
index da57339..6e8d790 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,8 @@
-This repository contains answers to the assignments of Advent of Coding 2022
+# Advent of Code 2022 - Assignment8 javascript
+## Description
+This problem is all about walking through a grid. In this solution, we look through an entire column and row until we find a node with height <= height.
+
+## References
+- https://www.w3schools.com/jsref/jsref_charat.asp
+- https://stackabuse.com/javascript-check-if-variable-is-a-number/
+- https://www.w3schools.com/jsref/jsref_abs.asp
\ No newline at end of file
diff --git a/index.html b/index.html
index 5cf1ba4..b89c9ad 100644
--- a/index.html
+++ b/index.html
@@ -8,6 +8,8 @@
Assignment:
+
+
Answer:
Provide input first
diff --git a/script.js b/script.js
index a6e2848..5df2cdc 100644
--- a/script.js
+++ b/script.js
@@ -1,12 +1,14 @@
const ASSIGNMENT = 'assignment';
const ANSWER = 'answer';
+const ALGORITHM_CHECKBOX = 'algorithm';
const NEWLINE_CHARACTER = '\n';
/**
* Main function
*/
-window.onload = function() {
- document.getElementById(ASSIGNMENT).addEventListener("input", calculateAnswer);
+window.onload = function () {
+ document.getElementById(ASSIGNMENT).addEventListener("input", calculateAnswer);
+ document.getElementById(ALGORITHM_CHECKBOX).addEventListener("click", calculateAnswer);
}
/**
@@ -15,7 +17,9 @@ window.onload = function() {
*/
function calculateAnswer(event) {
console.info("Calculating answer for input...");
- let answer = algorithm(event.target.value);
+ let assignment = document.getElementById(ASSIGNMENT).value;
+ let getHighestScenicScore = document.getElementById(ALGORITHM_CHECKBOX).checked;
+ let answer = algorithm(assignment, getHighestScenicScore);
document.getElementById(ANSWER).innerText = answer;
}
@@ -25,9 +29,106 @@ function calculateAnswer(event) {
* @param assignment the input from the assignment.
* @return string the answer
*/
-function algorithm(assignment) {
- let lines = assignment.trim().split(NEWLINE_CHARACTER);
- console.info("Linecount:" + lines.length);
+function algorithm(assignment, getHighestScenicScore) {
+ let lines = assignment.trim().split(NEWLINE_CHARACTER);
+ console.info("Linecount:" + lines.length);
- // TODO: implement assignment
+ let visibleTreeCount = 0;
+ let highestScenicScore = 0;
+
+ for (let i = 0; i < lines.length; i++) {
+ let row = lines[i].trim();
+
+ for (let j = 0; j < row.length; j++) {
+ if (i <= 0 || i >= lines.length - 1 || j <= 0 || j >= row.length - 1) { // Edge node
+ //console.debug("Edge node found.");
+ visibleTreeCount++;
+ continue;
+ }
+
+ let height = parseInt(lines[i].charAt(j));
+ if (!walkRowVisible(height, j, row) && !walkColumnVisible(height, i, j, lines)) {
+ console.log("Found invisible tree, height:" + height + ", i:" + i + ", j:" + j);
+ visibleTreeCount--;
+ }
+
+ if (getHighestScenicScore) {
+ let scenicScore = walkRowCount(height, j, row) * walkColumnCount(height, i, j, lines);
+ if (scenicScore > highestScenicScore) {
+ console.debug("Found new highest scenic score: " + scenicScore);
+ highestScenicScore = scenicScore;
+ }
+ }
+
+ // Tree is on edge.
+ visibleTreeCount++;
+ }
+ }
+
+ if (getHighestScenicScore) {
+ return "Highest scenic score: " + highestScenicScore;
+ }
+
+ return "Amount of visible trees in the grid: " + visibleTreeCount;
+}
+
+function walkColumnCount(height, index, rowIndex, column) {
+ return walkCount(height, index, column, false, rowIndex);
+}
+
+function walkRowCount(height, index, row) {
+ return walkCount(height, index, row, true, -1);
+}
+
+function walkColumnVisible(height, index, rowIndex, column) {
+ return walkVisible(height, index, column, false, rowIndex);
+}
+
+function walkRowVisible(height, index, row) {
+ return walkVisible(height, index, row, true, -1);
+}
+
+function walkCount(height, index, line, isRow, rowIndex) {
+ let visibleLeftCount = __walkHelper(height, index, line, isRow, -1, rowIndex, 0);
+ let visibleRightCount = __walkHelper(height, index, line, isRow, 1, rowIndex, 0);
+
+ return visibleLeftCount * visibleRightCount;
+}
+
+function walkVisible(height, index, line, isRow, rowIndex) {
+ let visibleLeft = __walkHelper(height, index, line, isRow, -1, rowIndex);
+ let visibleRight = __walkHelper(height, index, line, isRow, 1, rowIndex);
+
+ return visibleLeft || visibleRight;
+}
+
+function __walkHelper(height, index, line, isRow, direction, rowIndex, count) {
+ if (direction == 0) {
+ console.error("Invalid direction 0 in __walkhelper");
+ return -1;
+ }
+
+ direction = direction / Math.abs(direction);
+
+ // Edge reached
+ if ((direction < 0 && index <= 0) || (direction > 0 && index >= line.length - 1)) {
+ return (count == undefined) ? true : count;
+ }
+
+ let nextIndex = index + direction;
+ let nextHeightCharacter = (isRow) ? line.charAt(nextIndex) : line[nextIndex].trim().charAt(rowIndex);
+ let nextHeight = parseInt(nextHeightCharacter);
+
+ if (isNaN(height) || isNaN(nextHeightCharacter)) {
+ console.error("Invalid height found, height:" + height + ", nextHeight: " + nextHeightCharacter);
+ return -1;
+ }
+
+ if (height <= nextHeight) {
+ if (count == undefined)
+ return false;
+ return count + 1;
+ }
+
+ return __walkHelper(height, nextIndex, line, isRow, direction, rowIndex, (count !=undefined)? count + 1 : undefined);
}
\ No newline at end of file
diff --git a/style.css b/style.css
index f39a6bd..861cba6 100644
--- a/style.css
+++ b/style.css
@@ -6,6 +6,10 @@ body {
font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
}
+ textarea {
+ display: block;
+ }
+
#answer {
color: purple
}