//当你真的专注时,环境就不会影响到你。//永远不要当分母
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<vector>
#include<queue>
#include<stack>
using namespace std;
const int maxn=40;
stack<int> s;
vector<int> op;
int pre[maxn],in[maxn];
int preL,preR,inL,inR;
struct node
{
node* lchild;
node* rchild;
int data;
};
node* create(int preL,int preR,int inL,int inR)
{
if(preL>preR)
return NULL;
node* root=new node;
root->data=pre[preL];
int i;
for(i=inL;i<=inR;i++)
{
if(in[i]==pre[preL])
break;
}
int numleft=i-inL;
root->lchild=create(preL+1,preL+numleft,inL,i-1);
root->rchild=create(preL+numleft+1,preR,i+1,inR);
return root;
}
/*void level_traverse(node* root)
{
queue<node*> q;
q.push(root);
while(!q.empty())
{
node* top=q.front();
q.pop();
op.push_back(top->data);
if(top->lchild!=NULL)
q.push(top->lchild);
if(top->rchild!=NULL)
q.push(top->rchild);
}
}*/
void postorder(node* root)
{
if(root==NULL)
return;
postorder(root->lchild);
postorder(root->rchild);
op.push_back(root->data);
}
int main()
{
int n;
char str[5];
int j=0,k=0;
int temp;
scanf("%d",&n);
for(int i=0;i<2*n;i++)
{
scanf("%s",str);
if(strcmp(str,"Push")==0)
{
scanf("%d",&temp);
pre[j++]=temp;
s.push(temp);
}
else
{
in[k++]=s.top();
s.pop();
}
}
node* root=create(0,n-1,0,n-1);
postorder(root);
for(int i=0;i<op.size()-1;i++)
{
printf("%d ",op[i]);
}
printf("%d",op[op.size()-1]);
system("pause");
return 0;
}
PAT 1086
最新推荐文章于 2021-07-13 16:41:01 发布