/** * Returns the keys in the BST in level order (for debugging). * * @return the keys in the BST in level order traversal */ private Iterable<Point2D> levelOrder() { Queue<Point2D> keys = new Queue<Point2D>(); Queue<Node> queue = new Queue<Node>(); queue.enqueue(root); while (!queue.isEmpty()) { Node x = queue.dequeue(); if (x == null) { continue; } keys.enqueue(x.key); queue.enqueue(x.left); queue.enqueue(x.right); } return keys; }
public FastCollinearPoints( Point[] points) { // finds all line segments containing 4 or more points if (points == null) throw new NullPointerException(); for (int i = 0; i < points.length; i++) { if (points[i] == null) throw new NullPointerException(); } lineSegments = new Queue<LineSegment>(); for (int i = 0; i < points.length; i++) { // copy natural sorted array Point[] cPoints = new Point[points.length]; for (int j = 0; j < points.length; j++) { if (i != j && points[i].compareTo(points[j]) == 0) throw new IllegalArgumentException(); cPoints[j] = points[j]; } // sort by slope with points[i] Arrays.sort(cPoints, points[i].slopeOrder()); Point largest = cPoints[0]; Point smallest = cPoints[0]; int ccount = 1; for (int j = 1; j < points.length; j++) { if (points[i].slopeTo(cPoints[j - 1]) == points[i].slopeTo(cPoints[j])) { if (smallest.compareTo(cPoints[j]) > 0) smallest = cPoints[j]; else if (largest.compareTo(cPoints[j]) < 0) largest = cPoints[j]; ccount++; } else { if (ccount >= 3 && points[i].compareTo(smallest) < 0) { lineSegments.enqueue(new LineSegment(points[i], largest)); segmentCount++; } ccount = 1; smallest = cPoints[j]; largest = cPoints[j]; } } if (ccount >= 3 && points[i].compareTo(smallest) < 0) { lineSegments.enqueue(new LineSegment(points[i], largest)); segmentCount++; } } }
public static void listFiles(File file, Queue<? super String> f_names, int indent) { if (file.isDirectory()) { File[] files = file.listFiles(); if (files == null) return; Arrays.stream(files).forEach(f -> listFiles(f, f_names, indent + 2)); } else if (file.isFile()) { String format_str = String.format("%%%ds%%s\n", indent); f_names.enqueue(String.format(format_str, "", file.getName())); } }
private ShortestPath findShortestPath(int v, int w) { if (!isValid(v)) { throw new java.lang.NullPointerException("Invalid v parameter"); } if (!isValid(w)) { throw new java.lang.NullPointerException("Ivalid w parameter"); } Queue<Integer> q = new Queue<Integer>(); boolean[] marked = new boolean[G.V()]; int[] distTo = new int[G.V()]; q.enqueue(v); q.enqueue(w); marked[v] = true; marked[w] = true; distTo[v] = 0; distTo[w] = 0; while (!q.isEmpty()) { int a = q.dequeue(); for (int b : G.adj(a)) { if (marked[b]) { int length = distTo[b] + distTo[a] + 1; ShortestPath sp = new ShortestPath(); sp.ancestor = b; sp.length = length; return sp; } distTo[b] = distTo[a] + 1; marked[b] = true; q.enqueue(b); } } return null; }
public LazyPrimMST(EdgeWeightedGraph G) { pq = new MinPQ<Edge>(G.E()); mst = new Queue<Edge>(); marked = new boolean[G.V()]; visit(G, 0); while (!pq.isEmpty()) { Edge e = pq.delMin(); int v = e.either(); int w = e.other(v); if (marked[v] && marked[w]) continue; mst.enqueue(e); if (!marked[v]) visit(G, v); else visit(G, w); } }
// all neighboring boards public Iterable<Board> neighbors() { Queue<Board> result = new Queue<>(); int[][] directions = new int[][] {{-1, 0}, {1, 0}, {0, -1}, {0, 1}}; // up, down, left, right for (int[] direc : directions) { Board board = new Board(this); boolean success = swap( board.copy, board.blankX, board.blankY, board.blankX + direc[0], board.blankY + direc[1]); if (success) { result.enqueue(board); } } return result; }
private void range( final Node node, final RectHV rect, final Queue<Point2D> ranged, final boolean vertical) { if (node == null) { return; } if (rect.contains(node.key)) { ranged.enqueue(node.key); range(node.left, rect, ranged, !vertical); range(node.right, rect, ranged, !vertical); } else { if (onTheLeft(node.key, rect, vertical)) { range(node.left, rect, ranged, !vertical); } else if (onTheRight(node.key, rect, vertical)) { range(node.right, rect, ranged, !vertical); } else { range(node.left, rect, ranged, !vertical); range(node.right, rect, ranged, !vertical); } } }