层次结构打印二叉树

#include <stdio.h>#include <stdlib.h>struct TreeNode{int val;TreeNode *left,*right;};//左子树的节点小于等于根节点,右子树的节点大于等于根节点TreeNode* InsertTree(TreeNode *root,int val){TreeNode *node;if(NULL == root){node = (TreeNode *)malloc(sizeof(TreeNode));node->val = val;node->left = NULL;node->right = NULL;return node;}else if(val <= root->val)root->left = InsertTree(root->left,val);elseroot->right = InsertTree(root->right,val);return root;}void DeleteTree(TreeNode *root){if(root->left)DeleteTree(root->left);if(root->right)DeleteTree(root->right);free(root);}//层次结构打印二叉树void PrintfTree(TreeNode *root,char level[]){printf("%s%d/n",level,root->val);char child_level[81];sprintf(child_level,"%s%s",level," ");if(root->left)PrintfTree(root->left,child_level);elseprintf("%s$/n",child_level);if(root->right)PrintfTree(root->right,child_level);elseprintf("%s$/n",child_level);return;}void main(){FILE *fin;TreeNode *root;int val;char fileName[81],level[81];printf("input the data file's name:/n");//scanf的格式,不是连续输入的时候不需要'/n'scanf("%s",fileName);fin = fopen(fileName,"r");root = NULL;while(fscanf(fin,"%d",&val) != EOF)root = InsertTree(root,val);fclose(fin);sprintf(level,"%s","");PrintfTree(root,level);DeleteTree(root);system("PAUSE");return;}