Problem:
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Binary Search Tree I

Search trees are data structures that support dynamic set operations including insert, search, delete and so on. Thus a search tree can be used both as a dictionary and as a priority queue.

Binary search tree is one of fundamental search trees. The keys in a binary search tree are always stored in such a way as to satisfy the following binary search tree property:

Let $x$ be a node in a binary search tree. If $y$ is a node in the left subtree of $x$, then $y.key \leq x.key$. If $y$ is a node in the right subtree of $x$, then $x.key \leq y.key$.

The following figure shows an example of the binary search tree.

For example, keys of nodes which belong to the left sub-tree of the node containing 80 are less than or equal to 80, and keys of nodes which belong to the right sub-tree are more than or equal to 80. The binary search tree property allows us to print out all the keys in the tree in sorted order by an inorder tree walk.

A binary search tree should be implemented in such a way that the binary search tree property continues to hold after modifications by insertions and deletions. A binary search tree can be represented by a linked data structure in which each node is an object. In addition to a key field and satellite data, each node contains fields left, right, and p that point to the nodes corresponding to its left child, its right child, and its parent, respectively.

To insert a new value $v$ into a binary search tree $T$, we can use the procedure insert as shown in the following pseudo code. The insert procedure is passed a node $z$ for which $z.key = v$, $z.left = NIL$, and $z.right = NIL$. The procedure modifies $T$ and some of the fields of $z$ in such a way that $z$ is inserted into an appropriate position in the tree.

1 insert(T, z)
2 y = NIL // parent of x
3 x = 'the root of T'
4 while x ≠ NIL
5 y = x // set the parent
6 if z.key < x.key
7 x = x.left // move to the left child
8 else
9 x = x.right // move to the right child
10 z.p = y
11
12 if y == NIL // T is empty
13 'the root of T' = z
14 else if z.key < y.key
15 y.left = z // z is the left child of y
16 else
17 y.right = z // z is the right child of y

Write a program which performs the following operations to a binary search tree $T$.

insert $k$: Insert a node containing $k$ as key into $T$.

print: Print the keys of the binary search tree by inorder tree walk and preorder tree walk respectively.

You should use the above pseudo code to implement the insert operation. $T$ is empty at the initial state.

Input

In the first line, the number of operations $m$ is given. In the following $m$ lines, operations represented by insert $k$ or print are given.

Output

For each print operation, print a list of keys obtained by inorder tree walk and preorder tree walk in a line respectively. Put a space character before each key.

Constraints

The number of operations $\leq 500,000$

The number of print operations $\leq 10$.

$-2,000,000,000 \leq key \leq 2,000,000,000$

The height of the binary tree does not exceed 100 if you employ the above pseudo code.

The keys in the binary search tree are all different.

Sample Input 1

8
insert 30
insert 88
insert 12
insert 1
insert 20
insert 17
insert 25
print

Sample Output 1

1 12 17 20 25 30 88
30 12 1 20 17 25 88

Reference

Introduction to Algorithms, Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. The MIT Press.

Solution in JAVA (judge verdict: Time Limit Exceeded)

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.TreeSet;
 
// insert ???????????????Binary Tree
// ?????????parentind = -1??¨????????????
class Treenode{
  int key;
  int leftind;
  int rightind;
  int oyaind;
  boolean havevalue;
  boolean haveleft;
  boolean haveright;

  Treenode(){
    haveleft = false;
    haveright = false;
    havevalue = false;
  }
}

public class Main {
  public static void main(String[] args) {
    InputReader sc = new InputReader(System.in);
 
    int comnum = sc.nextInt();
    Treenode[] tree = new Treenode[comnum];
    for(int i = 0; i < comnum; i++){
      tree[i] = new Treenode();
    }

// ?????£???????????????print??§???????????¨???????????????????????°??????
    int insertcount = 0;
    for(int comind = 0; comind < comnum; comind++){
      String comstr = sc.nextStr();
      if(comstr.charAt(0) == 'i'){// insert
        int insertvalue = sc.nextInt();
        int nownodeind = 0;
        int parentind = -1;
        while(tree[nownodeind].havevalue){
          if(tree[nownodeind].key < insertvalue){
            if(tree[nownodeind].haveright){
              parentind = nownodeind;
              nownodeind = tree[nownodeind].rightind;
            }else{
              parentind = nownodeind;
              tree[nownodeind].haveright = true;
              tree[nownodeind].rightind = insertcount;
              nownodeind = insertcount;
            }
          }else{
              parentind = nownodeind;
            if(tree[nownodeind].haveleft){
              nownodeind = tree[nownodeind].leftind;
            }else{
              parentind = nownodeind;
              tree[nownodeind].haveleft = true;
              tree[nownodeind].leftind = insertcount;
              nownodeind = insertcount;
            }
          }
        }

        tree[nownodeind].oyaind = parentind;
        tree[nownodeind].havevalue = true;
        tree[nownodeind].key = insertvalue;
        insertcount++;
      }else{// print
        //????????????????????????
        boolean[] acheck = new boolean[insertcount];
        for(int i = 0; i < insertcount; i++){
          acheck[i] = false;
        }
        int nownodeind = 0;
        int nowprinted = 0;
        while(nowprinted < insertcount){
          if(tree[nownodeind].haveleft && tree[nownodeind].haveright){//????????????????????´???
            if(acheck[nownodeind]){//????????????????????????????????´???
              if(acheck[tree[nownodeind].rightind]){//????????????????????????=?????????????????\???????????????
                nownodeind = tree[nownodeind].oyaind;
              }else{
                nownodeind = tree[nownodeind].rightind;
              }
            }else{//???????????????????????´???
              if(acheck[tree[nownodeind].leftind]){//?????????????????????????????´???
                System.out.printf(" %d", tree[nownodeind].key);
                acheck[nownodeind] = true;
                nowprinted++;
                nownodeind = tree[nownodeind].rightind;
              }else{
                nownodeind = tree[nownodeind].leftind;
              }
            }
          }else if(tree[nownodeind].haveleft){//??????????????????????????´???
            if(acheck[tree[nownodeind].leftind]){
              System.out.printf(" %d", tree[nownodeind].key);
              acheck[nownodeind] = true;
              nowprinted++;
              nownodeind = tree[nownodeind].oyaind;
            }else{
              nownodeind = tree[nownodeind].leftind;
            }
          }else if(tree[nownodeind].haveright){//??????????????????????????´???
            if(acheck[nownodeind]){
              if(acheck[tree[nownodeind].rightind]){
                nownodeind = tree[nownodeind].oyaind;
              }else{
                nownodeind = tree[nownodeind].rightind;
              }
            }else{
              System.out.printf(" %d", tree[nownodeind].key);
              acheck[nownodeind] = true;
              nowprinted++;
              nownodeind = tree[nownodeind].rightind;
            }
          }else{//??????????????´???(=????????´???)
            System.out.printf(" %d", tree[nownodeind].key);
            acheck[nownodeind] = true;
            nowprinted++;
            nownodeind = tree[nownodeind].oyaind;
          }
        }

        System.out.println("");

        
        //?¬??????????????????????
        boolean[] bcheck = new boolean[insertcount];
        for(int i = 0; i < insertcount; i++){
          bcheck[i] = false;
        }
        nownodeind = 0;
        nowprinted = 0;

        while(nowprinted < insertcount){
          if(tree[nownodeind].haveleft && tree[nownodeind].haveright){//????????????????????´???
            if(bcheck[nownodeind]){//??????????????????????????´???
              if(bcheck[tree[nownodeind].rightind]){//???????????????????????????
                nownodeind = tree[nownodeind].oyaind;
              }else{
                nownodeind = tree[nownodeind].rightind;
              }
            }else{//??????????????????
              System.out.printf(" %d", tree[nownodeind].key);
              nowprinted++;
              bcheck[nownodeind] = true;
              nownodeind = tree[nownodeind].leftind;
            }
          }else if(tree[nownodeind].haveleft){//??????????????????????????´???
            if(bcheck[nownodeind]){
              nownodeind = tree[nownodeind].oyaind;
            }else{
              System.out.printf(" %d", tree[nownodeind].key);
              nowprinted++;
              bcheck[nownodeind] = true;
              nownodeind = tree[nownodeind].leftind;              
            }
          }else if(tree[nownodeind].haveright){//??????????????????????????´???
            if(bcheck[nownodeind]){
              nownodeind = tree[nownodeind].oyaind;
            }else{
              System.out.printf(" %d", tree[nownodeind].key);
              nowprinted++;
              bcheck[nownodeind] = true;
              nownodeind = tree[nownodeind].rightind;                            
            }
          }else{//??????????????´???(=????????´???)
            System.out.printf(" %d", tree[nownodeind].key);
            nowprinted++;
            bcheck[nownodeind] = true;
            nownodeind = tree[nownodeind].oyaind;
          }
        }

        System.out.println("");
      }
    }

  }
 
//nextChar ?????????????????????

//System.out.printf("? %d %d\n", i, j);

  
// LinkedList<Integer>[] setsu = new LinkedList[n];
// for(int i = 0; i < n; i++){
//   setsu[i] = new LinkedList<Integer>();
// } 

 //???????????????????????¬
  static class InputReader {
      private InputStream stream;
      private byte[] buf = new byte[1024];
      private int curChar;
      private int numChars;
      private SpaceCharFilter filter;

      public InputReader(InputStream stream) {
          this.stream = stream;
      }
 
      public int next() {
          if (numChars == -1)
              throw new InputMismatchException();
          if (curChar >= numChars) {
              curChar = 0;
              try {
                  numChars = stream.read(buf);
              } catch (IOException e) {
                  throw new InputMismatchException();
              }
              if (numChars <= 0)
                  return -1;
          }
          return buf[curChar++];
      }
 
      public String nextStr() {
        int c = next();
        while(isSpaceChar(c)){c = next();}
        StringBuffer str = new StringBuffer();
        do{
          str.append((char)c);
          c = next();
        }while(!isSpaceChar(c));
        return str.toString();
      }

      public char nextChar() {
        int c = next();
        while(isSpaceChar(c)){c = next();}
        char ret;
        do{
          ret = (char)c;
          c = next();
        }while(!isSpaceChar(c));
        return ret;
      }

      public int nextInt() {
          int c = next();
          while (isSpaceChar(c))
              c = next();
          int sgn = 1;
          if (c == '-') {
              sgn = -1;
              c = next();
          }
          int res = 0;
          do {
              if (c < '0' || c > '9')
                  throw new InputMismatchException();
              res *= 10;
              res += c - '0';
              c = next();
          } while (!isSpaceChar(c));
          return res * sgn;
      }
 
      public boolean isSpaceChar(int c) {
          if (filter != null)
              return filter.isSpaceChar(c);
          return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
      }
 
      public interface SpaceCharFilter {
          public boolean isSpaceChar(int ch);
      }
  }
}