Solution for assignment3.

README.md

@@ -1,13 +1,12 @@
-# Advent of Code 2022 - Assignment5 javascript
-This repository contains answers to the assignments of Advent of Coding 2022
+# Advent of Code 2022 - Assignment3 javascript solution
+This problem is all about searching for duplicates in strings. The solution is implemented using slice to split the string in half. 
+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_includes.asp
-- https://stackoverflow.com/questions/10261986/how-to-detect-string-which-contains-only-spaces
-- https://www.w3schools.com/jsref/jsref_indexof.asp
-- https://stackoverflow.com/questions/8073673/how-can-i-add-new-array-elements-at-the-beginning-of-an-array-in-javascript
-- https://stackoverflow.com/questions/966225/how-can-i-create-a-two-dimensional-array-in-javascript
-- https://www.w3schools.com/jsref/jsref_ceil.asp
-- https://stackoverflow.com/questions/30561056/console-log-a-multi-dimensional-array
-- https://teamtreehouse.com/community/removing-more-than-1-element-using-pop-and-shift-method
-- https://stackoverflow.com/questions/14723848/push-multiple-elements-to-array
+- https://stackoverflow.com/questions/94037/convert-character-to-ascii-code-in-javascript
+- https://stackoverflow.com/questions/20474257/split-string-into-two-parts
+- 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">All containers at once?</label>
+    <label for="algorithm">Solution by compartiment.</label> 
 
     <p>Answer:</p>
     <div id="answer">Provide input first</div>

script.js

@@ -1,10 +1,10 @@
 const ASSIGNMENT = 'assignment';
 const ANSWER = 'answer';
 const ALGORITHM_CHECKBOX = 'algorithm';
-const CONTAINER_NULL_CHARACTER=0;
-const INSTRUCTION_FROM='from';
-const INSTRUCTION_MOVE='move';
-const INSTRUCTION_TO='to';
+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';
 
 /**
@@ -22,8 +22,8 @@ window.onload = function() {
 function calculateAnswer(event) {
   console.info("Calculating answer for input...");
   let assignment = document.getElementById(ASSIGNMENT).value;
-  let allAtOnce = document.getElementById(ALGORITHM_CHECKBOX).checked;
-  let answer = algorithm(assignment, allAtOnce);
+  let byCompartiments = document.getElementById(ALGORITHM_CHECKBOX).checked;
+  let answer = algorithm(assignment, byCompartiments);
 
   document.getElementById(ANSWER).innerText = answer;
 }
@@ -31,137 +31,123 @@ function calculateAnswer(event) {
 /**
  * Calculate the answer to assignment.
  * @param assignment the input from the assignment.
- * @param allAtOnce should all containers be moved at once.
  * @return string the answer
  */
-function algorithm(assignment, allAtOnce) {
-    let lines = assignment.split(NEWLINE_CHARACTER);
-    let containerPlan = Array.from({length:(lines[0].length+1)/4}, () => [])
+function algorithm(assignment, byCompartiments) {
+    let priorityScoreSum = 0;
+    let lines = assignment.trim().split(NEWLINE_CHARACTER);
     console.info("Linecount:" + lines.length);
 
-    let parsec = true;
-    for(let i=0; i<lines.length; i++) {
-        if(parsec) {
+    let increment = (byCompartiments)? 1:3;
+    for(let i=0; i<lines.length; i+=increment) {
+        let inputs = [];
+        let rucksack = lines[i].replace(/\s/g, ''); // Remove whitespace
 
-            // Parse containers
-            let containerLine = lines[i];
-
-            // Skip numbers
-            if(containerLine[1] == '1') {
-                parsec = false;
-                i+=1;
-                console.table(containerPlan);
-                continue;
-            }
-
-            let containers = parseContainers(containerLine);
-            if(containers == -1) {
-                // invalid containerline
-                // TODO: error
-                console.error("Container parse failure.");
-                continue;
-            }
-
-            // Add containers
-            //console.debug(containers);
-            for(let j=0; j<containers.length; j++) {
-                let container = containers[j];
-                //console.debug(container);
-                if(container != CONTAINER_NULL_CHARACTER) {
-                    //console.debug(j);
-                    //console.debug(containerPlan);
-                    containerPlan[j].push(container);
-                }
-            }
-            //console.table(containerPlan);
+        if(byCompartiments) {
+            let compartiment1 = rucksack.slice(0, rucksack.length/2);
+            let compartiment2 = rucksack.slice(rucksack.length/2);
+            inputs = [compartiment1, compartiment2];
         } else {
-            // Parse instructions
-            let instructionLine = lines[i];
-            let instruction = parseInstruction(instructionLine);
+            inputs = [rucksack, lines[i+1].replace(/\s/g, ''), lines[i+2].replace(/\s/g, '')];
+        }
 
-            console.debug(instruction);
-            if(instruction == -1) {
-                // invalid instructionline
-                // TODO: error
-                console.error("Instruction parse failure.");
-                continue;
-            }
+        let duplicate = getDuplicateCharacter(inputs);
+        if(duplicate < 0) {
+            console.error(ERROR_MESSAGE_INVALID_INPUT_SIZE + inputs + " on line: " + i);
+        }
 
-            // Execute instruction
-            let movecount=0;
-            if(allAtOnce) {
-                while(instruction.move > 0) {
-                    let container = containerPlan[instruction.from].shift();
-                    containerPlan[instruction.to].unshift(container);
-                    instruction.move--;
-                    movecount++;
+        let priorityScore = getPriorityScore(duplicate);
+        if(priorityScore < 0) {
+            console.error(ERROR_MESSAGE_INVALID_ITEM_CHARACTER + duplicate + " on line: " + i);
+            continue;
+        }
+        priorityScoreSum += priorityScore;
+    }
+
+    return "SUM priorityscore: " + priorityScoreSum;
+}
+
+/**
+ * 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;
                 }
-                console.debug("moved:" + movecount);
-            } else {
-                let splicedContainers = containerPlan[instruction.from].splice(0, instruction.move);
-                containerPlan[instruction.to].unshift(...splicedContainers);
+                priorityScoreSum += priorityScore;
+                break;
             }
-
-            //console.table(containerPlan);
         }
     }
 
-    let result="";
-    for(let k=0; k<containerPlan.length; k++) {
-        result += containerPlan[k][0];
-    }
-
-    return "Top containers on the stack are: " + result;
+    return "SUM priorityscore: " + priorityScoreSum;
 }
 
-function parseInstruction(instructionLine) {
-    let instruction={
-        move:0,
-        from:0,
-        to:0,
-    }
-
-    instructionLine.replace(/\s/g, ''); // Remove whitespace
-    let fromIndex = instructionLine.indexOf(INSTRUCTION_FROM);
-    let moveIndex = instructionLine.indexOf(INSTRUCTION_MOVE);
-    let toIndex = instructionLine.indexOf(INSTRUCTION_TO);
-
-    // Validate
-    if(fromIndex < 0 || moveIndex < 0 || toIndex < 0) {
-        // Error
+/**
+ * Find duplicate character in inputs.
+ * @param string[] inputs the inputs to find duplicates in. 
+ * @return char the duplicate character
+ */
+function getDuplicateCharacter(inputs) {
+    console.debug("Checking inputs: " + inputs);
+    if(inputs.length < 2) {
         return -1;
     }
 
-    // TODO validate check for numbers after indices.
-
-    // Parse
-    instruction.move = parseInt(instructionLine.substring(moveIndex + INSTRUCTION_MOVE.length + 1, fromIndex));
-    instruction.from = parseInt(instructionLine.substring(fromIndex + INSTRUCTION_FROM.length + 1, toIndex)) -1;
-    instruction.to = parseInt(instructionLine.substring(toIndex + INSTRUCTION_TO.length + 1)) -1;
-
-    return instruction;
-}
-
-function parseContainers(containerLine) {
-    let containerLineLength = (containerLine.length+1);
-    //console.debug("Parse ContainerLine, length: " + containerLineLength);
-
-    if(!containerLine.includes('[') || !containerLine.includes(']') || containerLineLength % 4 != 0) {
-        return -1;
-    }
-
-    let containers = [];
-    for(let i=0; i<containerLineLength; i+=4) {
-        let containerLineSubString = containerLine.substring(i, i+4).trim();
-        let character = containerLineSubString[1];
-        if(containerLineSubString[0] != '[' || containerLineSubString[2] != ']') {
-                // Warning invalid container format
-                // TODO: warning
+    for(let item of inputs[0]) {
+        let duplicate = true
+        for(let j=1; j<inputs.length; j++) {
+            duplicate = duplicate && inputs[j].includes(item);
         }
 
-        containers.push((!character)? CONTAINER_NULL_CHARACTER: character);
+        if(duplicate) {
+            console.debug("Found duplicate: " + item);
+            return item;
+        }
     }
-    //console.debug(containers);
+}
 
-    return containers;
+/**
+ * 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(character == uppercase) { // Switch results for upper and lowercase characters
+        result -= CHARCODE_UPPER_CORRECTION;
+        character = lowercase;
+    } else {
+        character = uppercase;
+    }
+
+    result += character.charCodeAt() - CHARCODE_START;
+
+    return result;
 }