A - Binary Tree Traversals
记一个模板
#include<iostream> using namespace std; typedef struct Tree{ Tree *left; Tree *right; int value; }Tree; Tree *root; Tree* create(int *preorder,int *inorder,int n) { Tree *temp; for(int i=0;i<n;i++) { if(preorder[0]==inorder[i]) { temp=(Tree*)malloc(sizeof(Tree)); temp->value=inorder[i]; temp->left=create(preorder+1,inorder,i); temp->right=create(preorder+i+1,inorder+i+1,n-i-1); return temp; } } return NULL; } void postOrder(Tree *postTree) { if(postTree!=NULL) { postOrder(postTree->left); postOrder(postTree->right); if(postTree==root) printf("%d\n",postTree->value); else printf("%d ",postTree->value); } } int main() { int n; int preorder[2010],inorder[2010]; while(scanf("%d",&n)!=EOF) { root=NULL; for(int i=0;i<n;i++) scanf("%d",&preorder[i]); for(int i=0;i<n;i++) scanf("%d",&inorder[i]); root=create(preorder,inorder,n); postOrder(root); } return 0;