Solution for assignment3.

README.md

@@ -1,8 +1,12 @@
-# Advent of Code 2022 - Assignment8 javascript
+# Advent of Code 2022 - Assignment3 javascript solution
-## Description
+This problem is all about searching for duplicates in strings. The solution is implemented using slice to split the string in half. 
-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.
+The priority is retrieved using the ASCII charcode character for convienence. How to retrieve inputs differs between part1 and 2, therefore a checkbox is provided to toggle between different parsing methods.
 
 ## References
-- https://www.w3schools.com/jsref/jsref_charat.asp
+- https://stackoverflow.com/questions/94037/convert-character-to-ascii-code-in-javascript
-- https://stackabuse.com/javascript-check-if-variable-is-a-number/
+- https://stackoverflow.com/questions/20474257/split-string-into-two-parts
-- https://www.w3schools.com/jsref/jsref_abs.asp
+- https://www.folkstalk.com/2022/10/find-common-characters-in-two-strings-javascript-with-code-examples.html
+- https://stackoverflow.com/questions/351409/how-to-append-something-to-an-array
+- https://stackoverflow.com/questions/9862761/how-to-check-if-character-is-a-letter-in-javascript
+- https://stackoverflow.com/questions/1966476/how-can-i-process-each-letter-of-text-using-javascript
+- https://www.w3schools.com/js/js_arrays.asp

index.html

@@ -9,7 +9,7 @@
     <p>Assignment:</p>
     <textarea rows="15" cols="50" id="assignment"></textarea>
     <input type="checkbox" id="algorithm"/>
-    <label for="algorithm">Highest scenic score?</label>
+    <label for="algorithm">Solution by compartiment.</label> 
 
     <p>Answer:</p>
     <div id="answer">Provide input first</div>

script.js

@@ -1,6 +1,10 @@
 const ASSIGNMENT = 'assignment';
 const ANSWER = 'answer';
 const ALGORITHM_CHECKBOX = 'algorithm';
+const CHARCODE_START=64;
+const CHARCODE_UPPER_CORRECTION=6;
+const ERROR_MESSAGE_INVALID_INPUT_SIZE = "Invalid input size, should be higher than 2 for: ";
+const ERROR_MESSAGE_INVALID_ITEM_CHARACTER = "Invalid item character found: ";
 const NEWLINE_CHARACTER = '\n';
 
 /**
@@ -18,8 +22,8 @@ window.onload = function () {
 function calculateAnswer(event) {
   console.info("Calculating answer for input...");
   let assignment = document.getElementById(ASSIGNMENT).value;
-  let getHighestScenicScore = document.getElementById(ALGORITHM_CHECKBOX).checked;
+  let byCompartiments = document.getElementById(ALGORITHM_CHECKBOX).checked;
-  let answer = algorithm(assignment, getHighestScenicScore);
+  let answer = algorithm(assignment, byCompartiments);
 
   document.getElementById(ANSWER).innerText = answer;
 }
@@ -29,106 +33,121 @@ function calculateAnswer(event) {
  * @param assignment the input from the assignment.
  * @return string the answer
  */
-function algorithm(assignment, getHighestScenicScore) {
+function algorithm(assignment, byCompartiments) {
+    let priorityScoreSum = 0;
     let lines = assignment.trim().split(NEWLINE_CHARACTER);
     console.info("Linecount:" + lines.length);
 
-  let visibleTreeCount = 0;
+    let increment = (byCompartiments)? 1:3;
-  let highestScenicScore = 0;
+    for(let i=0; i<lines.length; i+=increment) {
+        let inputs = [];
+        let rucksack = lines[i].replace(/\s/g, ''); // Remove whitespace
 
-  for (let i = 0; i < lines.length; i++) {
+        if(byCompartiments) {
-    let row = lines[i].trim();
+            let compartiment1 = rucksack.slice(0, rucksack.length/2);
+            let compartiment2 = rucksack.slice(rucksack.length/2);
+            inputs = [compartiment1, compartiment2];
+        } else {
+            inputs = [rucksack, lines[i+1].replace(/\s/g, ''), lines[i+2].replace(/\s/g, '')];
+        }
 
-    for (let j = 0; j < row.length; j++) {
+        let duplicate = getDuplicateCharacter(inputs);
-      if (i <= 0 || i >= lines.length - 1 || j <= 0 || j >= row.length - 1) { // Edge node
+        if(duplicate < 0) {
-        //console.debug("Edge node found.");
+            console.error(ERROR_MESSAGE_INVALID_INPUT_SIZE + inputs + " on line: " + i);
-        visibleTreeCount++;
+        }
+
+        let priorityScore = getPriorityScore(duplicate);
+        if(priorityScore < 0) {
+            console.error(ERROR_MESSAGE_INVALID_ITEM_CHARACTER + duplicate + " on line: " + i);
             continue;
         }
-
+        priorityScoreSum += priorityScore;
-      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) {
+    return "SUM priorityscore: " + priorityScoreSum;
-        let scenicScore = walkRowCount(height, j, row) * walkColumnCount(height, i, j, lines);
+}
-        if (scenicScore > highestScenicScore) {
+
-          console.debug("Found new highest scenic score: " + scenicScore);
+/**
-          highestScenicScore = scenicScore;
+ * Calculate the answer to assignment.
+ * @param assignment the input from the assignment.
+ * @return string the answer
+ */
+ function algorithm1(assignment) {
+    let priorityScoreSum = 0;
+    let lines = assignment.trim().split(NEWLINE_CHARACTER);
+    console.info("Linecount:" + lines.length);
+
+    for(let i=0; i<lines.length; i++) {
+        let rucksack = lines[i].replace(/\s/g, ''); // Remove whitespace
+        let compartiment1 = rucksack.slice(0, rucksack.length/2);
+        let compartiment2 = rucksack.slice(rucksack.length/2);
+
+        console.debug("Check rucksack" + i, ": " + rucksack + " \n with compartiment1: " + compartiment1 + "\n and compartiment2: " + compartiment2);
+        
+        for(item of compartiment2) {
+            if(compartiment1.includes(item)) {
+                console.debug("Found duplicate: " + item + " in rucksack" + i);
+                let priorityScore = getPriorityScore(item);
+                if(priorityScore < 0) {
+                    console.error(ERROR_MESSAGE_INVALID_ITEM_CHARACTER + item + " on line: " + i);
+                    continue;
+                }
+                priorityScoreSum += priorityScore;
+                break;
+            }
         }
     }
 
-      // Tree is on edge.
+    return "SUM priorityscore: " + priorityScoreSum;
-      visibleTreeCount++;
-    }
 }
 
-  if (getHighestScenicScore) {
+/**
-    return "Highest scenic score: " + highestScenicScore;
+ * Find duplicate character in inputs.
-  }
+ * @param string[] inputs the inputs to find duplicates in. 
-
+ * @return char the duplicate character
-  return "Amount of visible trees in the grid: " + visibleTreeCount;
+ */
-}
+function getDuplicateCharacter(inputs) {
-
+    console.debug("Checking inputs: " + inputs);
-function walkColumnCount(height, index, rowIndex, column) {
+    if(inputs.length < 2) {
-  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);
+    for(let item of inputs[0]) {
-
+        let duplicate = true
-  // Edge reached
+        for(let j=1; j<inputs.length; j++) {
-  if ((direction < 0 && index <= 0) || (direction > 0 && index >= line.length - 1)) {
+            duplicate = duplicate && inputs[j].includes(item);
-    return (count == undefined) ? true : count;
         }
 
-  let nextIndex = index + direction;
+        if(duplicate) {
-  let nextHeightCharacter = (isRow) ? line.charAt(nextIndex) : line[nextIndex].trim().charAt(rowIndex);
+            console.debug("Found duplicate: " + item);
-  let nextHeight = parseInt(nextHeightCharacter);
+            return item;
+        }
+    }
+}
 
-  if (isNaN(height) || isNaN(nextHeightCharacter)) {
+/**
-    console.error("Invalid height found, height:" + height + ", nextHeight: " + nextHeightCharacter);
+ * Returns priorityscore for given character.
+ * @param char character the character
+ * @return int the priorityscore for character or -1 if invalid 
+ */
+function getPriorityScore(character) {
+    let result=0;
+    let uppercase = character.toUpperCase();
+    let lowercase = character.toLowerCase();
+    
+    // validate character
+    if( uppercase == lowercase ) {
         return -1;
     }
     
-  if (height <= nextHeight) {
+    if(character == uppercase) { // Switch results for upper and lowercase characters
-    if (count == undefined)
+        result -= CHARCODE_UPPER_CORRECTION;
-      return false;
+        character = lowercase;
-    return count + 1;
+    } else {
+        character = uppercase;
     }
 
-  return __walkHelper(height, nextIndex, line, isRow, direction, rowIndex, (count !=undefined)? count + 1 : undefined);
+    result += character.charCodeAt() - CHARCODE_START;
+
+    return result;
 }