c_cpp 将根与叶数相加。给定仅包含0-9的数字的二叉树，每个根到叶路径可以表示数字。一个例子

Posted 2021-05-14

void root_to_leaves_path_sum(TreeNode *root, int curr, int &res) {
    if(!root) return;
    curr = 10 * curr + root->val;
    if(root->left == NULL && root->right == NULL) 
        res += curr;
    root_to_leaves_path_sum(root->left, curr, res);
    root_to_leaves_path_sum(root->right, curr, res);
}

int get_sum (TreeNode *r) {
    int res = 0, curr = 0;
    fun(r, curr, res);
    return res;
}