Extreme nodes in alternate order

PROBLEM :

Given a binary tree, print nodes of extreme corners of each level but in alternate order.

Example:
Binary Tree

For above tree, the output is

1 2 7 8 31
– print rightmost node of 1st level
– print leftmost node of 2nd level
– print rightmost node of 3rd level
– print leftmost node of 4th level
– print rightmost node of 5th level



Input:
The task is to complete the method which takes one argument, root of the Tree. The struct node has a data part which stores the data, pointer to left child and pointer to right child.
There are multiple test cases. For each test case, this method will be called individually.


Output:
The function should print extreme nodes in alternte manner.

Constraints:
1 <=T<= 30
1 <=Number of nodes<= 100
1 <=Data of a node<= 1000

Example:
Input:
2
2
1 2 R 1 3 L
7
20 8 L 20 22 R 8 4 L 8 12 R 12 10 L 12 14 R 22 25 R



Output:
1 3
20 8 25 10

There are two test casess.  First case represents a tree with 3 nodes and 2 edges where root is 1, left child of 1 is 3 and right child of 1 is 2.   Second test case represents a tree with 7 edges and 8 nodes.

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SIMPLE c++ IMPLEMENTATION :(Using Auxilary arry)
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/*
struct Node
{
int data ;
struct Node *next ;
}       */

/* Function to print nodes of extreme corners
of each level in alternate order */

int height_tree(Node *) ;
void level_tree(Node *,int ,bool ,int* ) ;

void printExtremeNodes(Node* root)
{
    int h ;
    h=height_tree(root) ;
   
    int i,k ;
    k=-1 ;
    bool swap=true ;
   
    for(i=0;i<h;i++)
    {
        level_tree(root,i,swap,&k) ;
        k=-1 ;
        swap=!swap ;
    }
}

int height_tree(Node *root)
{
    if(root==NULL)
        return 0 ;
       
    int l,r ;
    l=height_tree(root->left) ;
    r=height_tree(root->right) ;
   
    return l>r?(l+1):(r+1) ;
}

void level_tree(Node *root,int level,bool swap,int *k)
{
    if(root==NULL)
        return ;
       
    if(level==0)
    {
        if((*k)==-1)
        {
            cout<<root->data<<" " ;
            (*k)=0 ;
        }
    }
    else
    {
        if(!swap)
        {
           level_tree(root->left,level-1,swap,&(*k)) ;
           level_tree(root->right,level-1,swap,&(*k)) ;
        }
        else
        {
            level_tree(root->right,level-1,swap,&(*k)) ;
            level_tree(root->left,level-1,swap,&(*k)) ;
        }
    }
}

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