Diameter and maximum distance between two nodes in a Binary tree.

/*
  Function to find out maximum distance between two nodes in a binary tree.
  Ds for tree could be found here: Ds for Tree
*/

public int height(Node root){

        if(root==null)

            return 0;

        else

            return (1+max(height(root.getLeft()),height(root.getRight())));

    }

    

    public int max(int a, int b){

        return a>b?a:b;

    }

    

    public int diameter(Node root){

        if(root==null)

            return 0;

        else{

            int lh=height(root.getLeft());

            int rh=height(root.getRight());

            

            int ld=diameter(root.getLeft());

            int rd=diameter(root.getRight());

            

            return( max(1+lh+rh,max(ld,rd)));  //add 1 to the result if counting current node as well.

        }           

    }