leetcode 117.填充每个节点的下一个右侧节点II

/*
// Definition for a Node.
class Node {
public:
    int val;
    Node* left;
    Node* right;
    Node* next;

    Node() : val(0), left(NULL), right(NULL), next(NULL) {}

    Node(int _val) : val(_val), left(NULL), right(NULL), next(NULL) {}

    Node(int _val, Node* _left, Node* _right, Node* _next)
        : val(_val), left(_left), right(_right), next(_next) {}
};
*/

class Solution {
public:
    Node* connect(Node* root) {
         queue<Node*> q;
         if(root!=NULL){
            q.push(root);
         }
         while(!q.empty()){
            int size=q.size();
            Node* cur;
            Node* curP;
            for(int i=0;i<size;i++){
                if(i==0){
                    curP=q.front();
                    q.pop();
                    cur=curP;

                }else{
                    cur=q.front();
                    q.pop();
                    curP->next=cur;
                    curP=curP->next;
                }
                if(cur->left!=NULL) q.push(cur->left);
                if(cur->right!=NULL) q.push(cur->right);

            }
            curP->next=NULL;
         }
         return root;
    }
};

同样的内容，可以再写一遍练习一下