use of com.pkumar7.trees.RootingTree.TreeNode in project Data-Structures-Algorithms by pankajgangwar.
the class A method increasingBSTRec.
public TreeNode increasingBSTRec(TreeNode root, TreeNode tail) {
if (root == null)
return tail;
TreeNode r_left = increasingBSTRec(root.left, root);
root.left = null;
TreeNode r_right = increasingBSTRec(root.right, tail);
root.right = r_right;
return r_left;
}
use of com.pkumar7.trees.RootingTree.TreeNode in project Data-Structures-Algorithms by pankajgangwar.
the class A method widthOfBinaryTree.
/*
* 662. Maximum Width of Binary Tree
* https://leetcode.com/problems/maximum-width-of-binary-tree/
*/
public int widthOfBinaryTree(TreeNode root) {
if (root == null)
return 0;
Queue<TreeNode> q = new LinkedList<>();
Map<TreeNode, Integer> map = new HashMap<>();
map.put(root, 1);
q.offer(root);
int maxWidth = 0;
while (!q.isEmpty()) {
int size = q.size();
int start = 0;
int end = 0;
for (int i = 0; i < size; i++) {
TreeNode curr = q.poll();
if (i == 0)
start = map.get(curr);
if (i == size - 1)
end = map.get(curr);
if (curr.left != null) {
q.offer(curr.left);
map.put(curr.left, 2 * map.get(curr));
}
if (curr.right != null) {
q.offer(curr.right);
map.put(curr.right, 2 * map.get(curr) + 1);
}
}
int currMax = end - start + 1;
maxWidth = Math.max(currMax, maxWidth);
}
return maxWidth;
}
use of com.pkumar7.trees.RootingTree.TreeNode in project Data-Structures-Algorithms by pankajgangwar.
the class B method lowestCommonAncestor.
/* 1676. Lowest Common Ancestor of a Binary Tree IV
* https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree-iv/
* */
public TreeNode lowestCommonAncestor(TreeNode root, TreeNode[] nodes) {
if (root == null)
return null;
for (TreeNode n : nodes) {
if (root == n) {
return root;
}
}
TreeNode l = lowestCommonAncestor(root.left, nodes);
TreeNode r = lowestCommonAncestor(root.right, nodes);
if (l != null && r == null)
return l;
if (l == null && r != null)
return r;
if (l != null && r != null)
return root;
return null;
}
use of com.pkumar7.trees.RootingTree.TreeNode in project Data-Structures-Algorithms by pankajgangwar.
the class Isomorphism method isIsomorphic.
/*
* AHU (Aho, Hopcroft, Ullman) algorithm uses clever serialization technique
* for representing a tree as a unique string.
* 1) Determine tree isomorphism in time O(|V|^2).
* 2) Uses complete history of degree spectrum of the vertex descendants as a complete
* invariant.
* */
public boolean isIsomorphic(LinkedList<Integer>[] graph1, LinkedList<Integer>[] graph2) {
TreeCenter centers1 = new TreeCenter();
List<Integer> a = centers1.findCenter(graph1);
List<Integer> b = centers1.findCenter(graph2);
System.out.println("Center for a " + a.get(0) + "\nCenter for b " + b.get(0));
RootingTree tree = new RootingTree();
TreeNode rootNode = tree.rootTree(graph1, a.get(0), null);
String tree1_encode = encode(rootNode);
System.out.println("tree1_encode = " + tree1_encode);
for (int centers : b) {
TreeNode root = tree.rootTree(graph2, centers, null);
String tree2_encode = encode(root);
System.out.println("tree2_encode = " + tree2_encode);
if (tree1_encode.equals(tree2_encode)) {
return true;
}
}
return false;
}
use of com.pkumar7.trees.RootingTree.TreeNode in project Data-Structures-Algorithms by pankajgangwar.
the class NovemberW3 method printSpiral.
/* Tree traversal spiral order using Stack*/
void printSpiral(TreeNode TreeNode) {
// Your code here
Stack<TreeNode> s1 = new Stack<>();
Stack<TreeNode> s2 = new Stack<>();
s1.push(TreeNode);
List<Integer> list = new ArrayList<>();
while (!s1.isEmpty() || !s2.isEmpty()) {
while (!s1.isEmpty()) {
TreeNode curr = s1.pop();
list.add(curr.val);
if (curr.right != null) {
s2.push(curr.right);
}
if (curr.left != null) {
s2.push(curr.left);
}
}
while (!s2.isEmpty()) {
TreeNode curr = s2.pop();
list.add(curr.val);
if (curr.left != null) {
s1.push(curr.left);
}
if (curr.right != null) {
s1.push(curr.right);
}
}
}
for (int ele : list) {
System.out.print(ele + " ");
}
}
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