Print all paths from root to leaf in a Binary tree

Question

Here is the code I wrote to print all paths of a Binary tree from root to leaf:

public static void printRootToLeaf(Node1 root, List list) {
           


        

Answer 1

The question here is how did you get the solution rather than did you get the solution. The performance is the key here. Create a tree object first..

class Node {

public Node left;
public Node right;
public Character val;

public Node(char val) {
    this.val = val;
}   

get all paths in list..

public List> printPath(Node root) {

    if (root == null) return new ArrayList>();

    List> left = printPath(root.left);
    List> right = printPath(root.right);

    left.addAll(right);

    for (LinkedList lst : left) {
        lst.addFirst(root);
    }
    if(left.size()==0){
        LinkedList lst= new LinkedList();
        lst.add(root);
        left.add(lst);
    }
    return left;

}

print all the paths now..

  Node root = new Node('a');
    System.out.println(root.val);
    root.left = new Node('b');
    root.left.left = new Node('c');
    root.left.right = new Node('d');
    root.right = new Node('e');
    root.right.left = new Node('f');
    root.right.right = new Node('g');
    root.right.right.left = new Node('h');

    List> allPaths = wc.printPath(root);

    for (LinkedList lst : allPaths) {
        for (Node node : lst)
            System.out.print(node.val==null ? "-" : node.val);
        System.out.println();
    }