剑指Offer21 二叉树的层序遍历

 /*************************************************************************
     > File Name: 21_PrintTreeTopToBottom.cpp
     > Author: Juntaran
     > Mail: [e-mail]
     > Created Time: 2016年08月30日 星期二 20时24分53秒
  ************************************************************************/

 #include <stdio.h>
 #include <stdlib.h>
 #include <malloc.h>
 #include <bits/stdc++.h>

 using namespace std;

 // 二叉树结构体
 struct TreeNode
 {
     int val;
     TreeNode* left;
     TreeNode* right;
 };

 // 层序遍历
 void PrintTreeTopToBottom(TreeNode* root)
 {
     if (root == NULL)
         return;

     vector<TreeNode*> vec;
     vec.push_back(root);

     int cur = ;
     while (cur < vec.size())
     {
         printf("%d ", vec[cur]->val);
         if (vec[cur]->left)
             vec.push_back(vec[cur]->left);
         if (vec[cur]->right)
             vec.push_back(vec[cur]->right);
         ++cur;
     }
     printf("\n");
 }

 TreeNode* createTree()
 {
     TreeNode* root = (TreeNode*)malloc(sizeof(TreeNode));
     root->val = ;
     root->left = (TreeNode*)malloc(sizeof(TreeNode));
     root->left->val = ;
     root->right = (TreeNode*)malloc(sizeof(TreeNode));
     root->right->val = ;
     root->right->left = NULL;
     root->right->right = NULL;
     root->left->left = (TreeNode*)malloc(sizeof(TreeNode));
     root->left->left->val = ;
     root->left->left->left = NULL;
     root->left->left->right = NULL;
     root->left->right = (TreeNode*)malloc(sizeof(TreeNode));
     root->left->right->val = ;
     root->left->right->left = (TreeNode*)malloc(sizeof(TreeNode));
     root->left->right->left->val = ;
     root->left->right->left->left = NULL;
     root->left->right->left->right = NULL;
     root->left->right->right = (TreeNode*)malloc(sizeof(TreeNode));
     root->left->right->right->val = ;
     root->left->right->right->left = NULL;
     root->left->right->right->right = NULL;

     return root;
 }

 int main()
 {
     TreeNode* test = createTree();
     PrintTreeTopToBottom(test);
 }