Level order traversal in spiral form.cpp

//Use two stacks//
void printSpiral(Node *root)
{
    if(root==NULL)
    return;
    
    stack<Node*> s1;
    stack<Node*> s2;
    
    s1.push(root);
    
    while(!s1.empty() || !s2.empty())
    {
        while(!s1.empty())
        {
            Node* temp=s1.top();
            s1.pop();
            cout<<temp->data<<" ";
            
            if(temp->right!=NULL)
            s2.push(temp->right);
            
            if(temp->left!=NULL)
            s2.push(temp->left);
        }
        
        while(!s2.empty())
        {
            Node *temp=s2.top();
            s2.pop();
            cout<<temp->data<<" ";
            
            if(temp->left!=NULL)
            s1.push(temp->left);
            
            if(temp->right!=NULL)
            s1.push(temp->right);
        }
    }
    
}