SumtreeDFS Vector

#include <iostream>
#include <vector>
#include <queue>
using namespace std;

int sumTreeDFS(vector<int>& tree, int index) {
    if (index >= tree.size()) {
        return 0;
    }

    cout << "Visiting node: " << tree[index] << endl;

    int leftIndex = 2 * index + 1;
    int rightIndex = 2 * index + 2;

    int leftSum = sumTreeDFS(tree, leftIndex);
    int rightSum = sumTreeDFS(tree, rightIndex);

    return tree[index] + leftSum + rightSum;
}