3月3日[Go_deep]Populating Next Right Pointers in Each Node

/**
 * Definition for binary tree with next pointer.
 * struct TreeLinkNode {
 *  int val;
 *  TreeLinkNode *left, *right, *next;
 *  TreeLinkNode(int x) : val(x), left(NULL), right(NULL), next(NULL) {}
 * };
 */
class Solution {
public:
    void connect(TreeLinkNode *root) {
        if (root == NULL) return;
        
        if (root->left != NULL)
        {
            root->left->next = root->right;
            
            TreeLinkNode *go_deep_left = root->left->right;
            TreeLinkNode *go_deep_right = (root->right != NULL)?(root->right->left):NULL;
            
            while (go_deep_left != NULL && go_deep_right != NULL)
            {
                go_deep_left->next = go_deep_right;
                
                go_deep_left = go_deep_left->right;
                go_deep_right = go_deep_right->left;
            }
        }
        
        connect(root->right);
        connect(root->left);
    }
};