Traversing a binary tree using a vector return type

Question

I am trying to traverse a templated AVLtree with a key value pair and return a vector of all the values.

When using a cout statement, I can tell that the function is correctly traversing the tree and it will return all values in the tree. However, when I try to add this to a vector and use it in another part of my program, only the root node has been stored.

    vector<s> treeTraversal(){
         return treeTraversal(root);
    }

    vector<s> treeTraversal(AVLNode<t, s> *node ){
        vector<s> temp;

        if(node != nullptr){
            treeTraversal(node -> left);
            treeTraversal(node -> right);
            temp.push_back(node -> vectorToBe);
        }

        return temp;
    }

I am intending to store all the returned values in a vector so I can access them in a later part of my program

Answer 1

I'd try something like this. You'll avoid creating a ton of vector<s>s in the stack.

vector<s> treeTraversal(){
     vector<s> result;
     treeTraversal(root, result);
     return result;
}

void treeTraversal(AVLNode<t, s> *node, vector<s>& visited ){
    if(node != nullptr){
        treeTraversal(node -> left, visited);
        treeTraversal(node -> right, visited);
        visited.push_back(node->vectorToBe);
    }
}