Diagonal traversal of binary tree

void diagonalPrint(Node *root)
{
   map<int,vector<Node*> >mp;
   int level=0;
   queue<Node*>q;
   q.push(root);
   while(!q.empty()){
        int s=q.size();
        for(int i=0;i<s;i++){
            Node *curr=q.front();
            q.pop();
            mp[level].push_back(curr);
            if(curr->left)
                q.push(curr->left);
            if(curr->right)
                q.push(curr->right);
            level++;
        }
        level=0;

   }
   for(auto it=mp.begin();it!=mp.end();it++){
       vector<Node *>v=it->second;
       for(int i=0;i<v.size();i++){
           cout<<v[i]->data<<" ";
       }
   }
}