public Main() { try { BufferedReader in; in = new BufferedReader(new InputStreamReader(System.in)); // Used for CCC int numLights = Integer.parseInt(in.readLine()); int[] states = new int[numLights]; for (int i = 0; i < numLights; i++) { states[i] = Integer.parseInt(in.readLine()); } ArrayDeque<Scenario> Q = new ArrayDeque<Scenario>(); HashMap<String, Integer> dp = new HashMap<String, Integer>(); int moves = 0; Q.addLast(new Scenario(states)); while (!Q.isEmpty()) { int size = Q.size(); for (int q = 0; q < size; q++) { Scenario temp = Q.removeFirst(); if (isEmpty(temp.states)) { System.out.println(moves); return; } else { for (int i = 0; i < temp.states.length; i++) { if (temp.states[i] == 0) { int[] newArr = Arrays.copyOf(temp.states, temp.states.length); newArr[i] = 1; newArr = fixArray(newArr); String arr = ""; for (int p = 0; p < newArr.length; p++) arr += newArr[p]; if (dp.get(arr) == null) { dp.put(arr, moves); Q.addLast(new Scenario(newArr)); } else { int val = dp.get(arr); if (val != 0 && moves < val) { dp.put(arr, moves); Q.addLast(new Scenario(newArr)); } } // outputArr(newArr); } } } } moves++; } } catch (IOException e) { System.out.println("IO: General"); } }
public List<List<Integer>> zigzagLevelOrder(TreeNode root) { List<List<Integer>> r = new ArrayList<List<Integer>>(); ArrayDeque<TreeNode> q = new ArrayDeque<TreeNode>(); if (root == null) return r; q.offer(root); boolean reversedOrder = false; while (!q.isEmpty()) { int len = q.size(); List<Integer> level = new LinkedList<Integer>(); for (int i = 0; i < len; i++) { TreeNode n = q.poll(); if (reversedOrder) level.add(0, n.val); else level.add(n.val); if (n.left != null) q.offer(n.left); if (n.right != null) q.offer(n.right); } r.add(level); reversedOrder = !reversedOrder; } return r; }
/** * Return the root hash of a binary tree with leaves at the given depths and with the given hash * val in each leaf. */ byte[] hashed(byte[] val, Integer... depths) { ArrayDeque<Integer> dstack = new ArrayDeque<Integer>(); ArrayDeque<byte[]> hstack = new ArrayDeque<byte[]>(); Iterator<Integer> depthiter = Arrays.asList(depths).iterator(); if (depthiter.hasNext()) { dstack.push(depthiter.next()); hstack.push(val); } while (depthiter.hasNext()) { Integer depth = depthiter.next(); byte[] hash = val; while (depth.equals(dstack.peek())) { // consume the stack hash = Hashable.binaryHash(hstack.pop(), hash); depth = dstack.pop() - 1; } dstack.push(depth); hstack.push(hash); } assert hstack.size() == 1; return hstack.pop(); }