标签：rate lin csdn case front stream .net must exactly
Suppose that all the keys in a binary tree are distinct positive integers. Given the postorder and inorder traversal sequences, you are supposed to output the level order traversal sequence of the corresponding binary tree.
Each input file contains one test case. For each case, the first line gives a positive integer N (≤), the total number of nodes in the binary tree. The second line gives the postorder sequence and the third line gives the inorder sequence. All the numbers in a line are separated by a space.
For each test case, print in one line the level order traversal sequence of the corresponding binary tree. All the numbers in a line must be separated by exactly one space, and there must be no extra space at the end of the line.
7
2 3 1 5 7 6 4
1 2 3 4 5 6 7
4 1 6 3 5 7 2
二叉树（根据后序、中序遍历还原二叉树）、BFS
参考博客：点击前往
1 #include<iostream> 2 #include<queue> 3 using namespace std; 4 struct Node{ 5 int data; 6 Node* lchild; 7 Node* rchild; 8 }; 9 10 int post[31]; 11 int in[31]; 12 int n; 13 14 //根据后序和中序遍历创建二叉树 15 Node* create(int postL,int postR,int inL,int inR){ 16 if(postL>postR){ 17 return NULL; 18 } 19 Node* root=new Node; 20 root->data=post[postR]; //后序的末尾是根 21 int k; 22 for(k=inL;k<=inR;k++){ //中序中寻找和后序末尾值相同的结点 23 if(in[k]==post[postR]){ 24 break; 25 } 26 } 27 int numLeft=k-inL; 28 root->lchild=create(postL,postL+numLeft-1,inL,k-1); 29 root->rchild=create(postL+numLeft,postR-1,k+1,inR); 30 return root; 31 } 32 33 int num=0; 34 //宽搜读取二叉树 35 void BFS(Node* root){ 36 queue<Node*> q; 37 q.push(root); 38 while(!q.empty()){ 39 num++; 40 Node* now=q.front(); 41 cout<<now->data; 42 if(num<n){ 43 cout<<" "; 44 } 45 q.pop(); 46 if(now->lchild!=NULL){ 47 q.push(now->lchild); 48 } 49 if(now->rchild!=NULL){ 50 q.push(now->rchild); 51 } 52 } 53 } 54 55 int main(){ 56 cin>>n; 57 for(int i=0;i<n;i++){ 58 cin>>post[i]; 59 } 60 for(int i=0;i<n;i++){ 61 cin>>in[i]; 62 } 63 Node* root=create(0,n-1,0,n-1); 64 BFS(root); 65 return 0; 66 }
标签：rate lin csdn case front stream .net must exactly
原文地址：https://www.cnblogs.com/orangecyh/p/10326683.html
