Add day 3 part i solution for tests

3/3_1.ts

@@ -1,5 +1,40 @@
-import { LoadInput } from "../common.ts";
-import * as util from "util";
+import { Inspect, LoadInput } from "../common.ts";
+
+/* Directions */
+const Directions = {
+    NORTH: {
+        X: 0,
+        Y: -1,
+    },
+    SOUTH: {
+        X: 0,
+        Y: 1,
+    },
+    EAST: {
+        X: 1,
+        Y: 0,
+    },
+    WEST: {
+        X: -1,
+        Y: 0,
+    },
+    NORTH_EAST: {
+        X: 1,
+        Y: -1,
+    },
+    NORTH_WEST: {
+        X: -1,
+        Y: -1,
+    },
+    SOUTH_EAST: {
+        X: 1,
+        Y: 1,
+    },
+    SOUTH_WEST: {
+        X: -1,
+        Y: 1,
+    },
+}
 
 const tests = [
     "467..114..",
@@ -14,11 +49,16 @@ const tests = [
     ".664.598..",
 ];
 
+// Build the find
 const testMap = BuildSchematicsMap(tests);
+// Find all possible parts
 let testParts = ParseSchematics(testMap);
-testParts = ValidateEngineParts(testParts);
+// Validate those parts
+testParts = ValidateEngineParts(testParts, testMap);
 
-console.log(util.inspect(testParts, { breakLength: Infinity, depth: 256, colors: true }));
+// Get out output
+const sumOfPartNumbers = testParts.reduce((accumulator, part) => accumulator += part.PartNumber, 0);
+console.log(`The sum of part numbers is: ${sumOfPartNumbers}`);
 
 /**
  * Parse the schematics to find all possible Engine Parts
@@ -88,11 +128,76 @@ function ParseSchematics(schematicsMap: string[][]): EnginePart[] {
  * symbol other than `.`.
  *
  * @param {EnginePart[]} potentialParts All potential Engine Parts
+ * @param {string[][]} schematicsMap A 2D grid of characters making up a schematic
  * @returns {EnginePart[]} A filtered list of all valid Engine Parts
  */
-function ValidateEngineParts(potentialParts: EnginePart[]): EnginePart[] {
+function ValidateEngineParts(potentialParts: EnginePart[], schematicsMap: string[][]): EnginePart[] {
+    const validParts: EnginePart[] = [];
+
+    for (const part of potentialParts) {
+        for (const point of part.Coordinates) {
+            if (BordersASymbol(point, schematicsMap)) {
+                validParts.push(part);
+                break;
+            }
+        }
+    }
+    return validParts;
+}
 
-    return [];
+/**
+ * Check if a point on the schematics map borders a symbol
+ *
+ * A symbol is any character other than a digit or a period.
+ *
+ * @param point A point on the schematics map
+ * @param schematicsMap A 2D grid of characters making up a schematic
+ * @returns {boolean} Whether the point borders a symbol or not
+ */
+function BordersASymbol(point: Vector2, schematicsMap: string[][]): boolean {
+    // Initialize all border chars as NOPs
+    let northernBorder   =  ".";
+    let easternBorder    =  ".";
+    let southernBorder   =  ".";
+    let westernBorder    =  ".";
+    let northEastBorder  =  ".";
+    let northWestBorder  =  ".";
+    let southEastBorder  =  ".";
+    let southWestBorder  =  ".";
+    // Check what borders exist
+    const northExists = !!schematicsMap[point.Y + Directions.NORTH.Y];
+    const southExists = !!schematicsMap[point.Y + Directions.SOUTH.Y];
+    const eastExists = !!schematicsMap[point.Y][point.X + Directions.EAST.X];
+    const westExists = !!schematicsMap[point.Y][point.X + Directions.WEST.X];
+    // Find the border chars
+    if(northExists) {
+        northernBorder = schematicsMap[point.Y + Directions.NORTH.Y][point.X + Directions.NORTH.X];
+        if(eastExists) {
+            northEastBorder = schematicsMap[point.Y + Directions.NORTH_EAST.Y][point.X + Directions.NORTH_EAST.X];
+        }
+        if(westExists) {
+            northWestBorder = schematicsMap[point.Y + Directions.NORTH_WEST.Y][point.X + Directions.NORTH_WEST.X];
+        }
+    }
+    if(southExists) {
+        southernBorder = schematicsMap[point.Y + Directions.SOUTH.Y][point.X + Directions.SOUTH.X];
+        if(eastExists) {
+            southEastBorder = schematicsMap[point.Y + Directions.SOUTH_EAST.Y][point.X + Directions.SOUTH_EAST.X];
+        }
+        if(westExists) {
+            southWestBorder = schematicsMap[point.Y + Directions.SOUTH_WEST.Y][point.X + Directions.SOUTH_WEST.X];
+        }
+    }
+    if (eastExists) {
+        easternBorder = schematicsMap[point.Y + Directions.EAST.Y][point.X + Directions.EAST.X];
+    }
+    if (westExists) {
+        westernBorder = schematicsMap[point.Y + Directions.WEST.Y][point.X + Directions.WEST.X];
+    }
+    // Combine all bordering characters into one long string
+    const allBorders = northernBorder + easternBorder + southernBorder + westernBorder + northEastBorder + northWestBorder + southEastBorder + southWestBorder;
+
+    return /[^0-9\.]/.test(allBorders);
 }
 
 /**
@@ -127,4 +232,4 @@ type SchematicsSymbol = {
 type Vector2 = {
     X: number,
     Y: number,
-};
+};