feat: sorta works

csci/knightsTravials.js

@@ -0,0 +1,155 @@
+class Node {
+    constructor() {
+        this.distance = null;
+        this.predecessor = null;
+    }
+}
+
+class Queue {
+    constructor() {
+        this.queue = [];
+    }
+
+    enqueue(thing) {
+        this.queue.push(thing);
+    }
+
+    dequeue() {
+        return this.queue.shift();
+    }
+
+    isEmpty() {
+        return this.queue.length === 0;
+    }
+}
+
+class Graph {
+    constructor(columns, rows) {
+        this.adjMatrix = [];
+        this.rows = rows;
+        this.columns = columns;
+
+        // Build the adj list
+        this.buildAdjList();
+    }
+    buildAdjList() {
+        this.adjList = [];
+
+        // Possible knight moves relative to its current position
+        const moves = [
+            [-1, -2],
+            [-2, -1],
+            [-2, 1],
+            [-1, 2],
+            [1, -2],
+            [2, -1],
+            [2, 1],
+            [1, 2],
+        ];
+
+        for (let y = 0; y < this.rows; y++) {
+            let rowData = [];
+            for (let x = 0; x < this.columns; x++) {
+                let adjPositions = [];
+
+                // Generate adjacent positions for the current square
+                for (const [dx, dy] of moves) {
+                    const newX = x + dx;
+                    const newY = y + dy;
+
+                    // Check if the new position is within the board boundaries
+                    if (
+                        newX >= 0 &&
+                        newX < this.columns &&
+                        newY >= 0 &&
+                        newY < this.rows
+                    ) {
+                        adjPositions.push([newX, newY]);
+                    }
+                }
+
+                rowData.push(adjPositions);
+            }
+            this.adjList.push(rowData);
+        }
+    }
+
+    knightMoves(start, finish) {
+        this.bfsInfo = [];
+        let itemFound = false;
+        this.start = start;
+        this.finish = finish;
+
+        for (let i = 0; i < this.columns; i++) {
+            this.bfsInfo[i] = [];
+            for (let j = 0; j < this.rows; j++) {
+                this.bfsInfo[i][j] = new Node();
+            }
+        }
+
+        // This is to mark where we're starting the loop
+        this.bfsInfo[start[0]][start[1]].distance = 0;
+
+        // instantiate the queue
+        let queue = new Queue();
+        queue.enqueue(start);
+
+        while (!queue.isEmpty() && !itemFound) {
+            let vertex = queue.dequeue();
+            if (vertex[0] === finish[0] && vertex[1] === finish[1]) {
+                itemFound = true;
+                break;
+            }
+
+            for (
+                let i = 0;
+                i < this.adjList[vertex[0]][vertex[1]].length;
+                i++
+            ) {
+                let neighbor = this.adjList[vertex[0]][vertex[1]][i];
+                let x = neighbor[0];
+                let y = neighbor[1];
+
+                if (this.bfsInfo[x][y].distance === null) {
+                    this.bfsInfo[x][y].distance =
+                        this.bfsInfo[vertex[0]][vertex[1]].distance + 1;
+                    this.bfsInfo[x][y].predecessor = [vertex[0], vertex[1]];
+                }
+
+                queue.enqueue(neighbor);
+            }
+        }
+    }
+
+    lookAtBfs() {
+        this.path = [this.finish];
+
+        let queue = new Queue();
+        let x = this.finish[0];
+        let y = this.finish[1];
+
+        queue.enqueue(this.bfsInfo[x][y]);
+
+        while (!queue.isEmpty()) {
+            let current = queue.dequeue();
+
+            if (current.predecessor) {
+                this.path.unshift(current.predecessor);
+                x = current.predecessor[0];
+                y = current.predecessor[1];
+                let previousNode = this.bfsInfo[x][y];
+                queue.enqueue(previousNode);
+            }
+        }
+        return this.path;
+    }
+}
+
+let g = new Graph(8, 8);
+console.log(g.adjList[1][2]);
+g.knightMoves([0, 0], [7, 7]);
+console.log(g.lookAtBfs());
+g.knightMoves([0, 0], [3, 3]);
+console.log(g.lookAtBfs());
+g.knightMoves([3, 3], [4, 3]);
+console.log(g.lookAtBfs());