[数据结构]求二叉树的深度与宽度

  二叉树数据结构声明：

struct TreeNode
{
    int val;
    TreeNode *left;
    TreeNode *right;
};

  1、递归求二叉树深度

int getDepth(TreeNode *root)
{
    if (root == NULL)
    {
        return 0;
    }
    return getDepth(root->left) > getDepth(root->right) ?(getDepth(root->left) + 1) : (getDepth(root->right) + 1);
}

  宽度优先遍历，记录每一个层次的叶子节点，返回最大值

int getWidth(TreeNode *root)
{
    if (root == NULL)
    {
        return 0;
    }
    int width_up = 0;
    int temp = 0;
    int width_cur = 0;
    int width_res = 0;
    queue<TreeNode *> myQueue;
    myQueue.push(root);
    width_up = 1;
    width_res=1;
    TreeNode *temp_TreeNode = NULL;

    while (!myQueue.empty())
    {
        temp = width_up;
        while (temp != 0)
        {
            temp_TreeNode = myQueue.front();
            myQueue.pop();

            if (temp_TreeNode->left != NULL)
            {
                myQueue.push(temp_TreeNode->left);
            }

            if (temp_TreeNode->right != NULL)
            {
                myQueue.push(temp_TreeNode->right);
            }

            width_up--;
        }

        width_cur = myQueue.size();
        width_res = width_cur > width_res ? width_cur : width_res;
        width_up = width_cur;
    }

    return width_res;
}