Problem:
Binary Search Tree III

Write a program which performs the following operations to a binary search tree $T$ by adding delete operation to B: Binary Search Tree II.

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

find $k$: Report whether $T$ has a node containing $k$.

delete $k$: Delete a node containing $k$.

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

The operation delete $k$ for deleting a given node $z$ containing key $k$ from $T$ can be implemented by an algorithm which considers the following cases:

If $z$ has no children, we modify its parent $z.p$ to replace $z$ with NIL as its child (delete $z$).

If $z$ has only a single child, we "splice out" $z$ by making a new link between its child and its parent.

If $z$ has two children, we splice out $z$'s successor $y$ and replace $z$'s key with $y$'s key.

Input

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

Output

For each find $k$ operation, print "yes" if $T$ has a node containing $k$, "no" if not.

In addition, 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

18
insert 8
insert 2
insert 3
insert 7
insert 22
insert 1
find 1
find 2
find 3
find 4
find 5
find 6
find 7
find 8
print
delete 3
delete 7
print

Sample Output 1

yes
yes
yes
no
no
no
yes
yes
1 2 3 7 8 22
8 2 1 3 7 22
1 2 8 22
8 2 1 22

Reference

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

Solution in JAVA (judge verdict: Accepted)

import java.util.*;
import java.io.*;

public class Main {
	static class Node {
		int key = 0;
		Node parent = NIL;
		Node left = NIL;
		Node right = NIL;
	}
	static Node NIL = new Node();
	
	static class Tree {
		Node root = NIL;
	}
	
	public static void main(String[]  args) {
		int m = nextInt();
		
		Tree tree = new Tree();
		
		for (int i = 0; i < m; i ++) {
			next();
			switch (nextbuf[0]) {
				case 'i':
					insert(tree, nextInt());
					break;
				case 'f':
					int key = nextInt();
					System.out.println((find(tree, key).key == key) ? "yes": "no");
					break;
				case 'd':
					delete(tree, nextInt());
					break;
				default:
					inorder(tree.root);
					System.out.println();
					preorder(tree.root);
					System.out.println();
					break;
			}
		}
	}
	
	static void insert(Tree tree, int key) {
		Node z = new Node();
		z.key = key;
		Node y = NIL;
		
		y = find(tree, key);
		
		if (y == NIL) {
			tree.root = z;
		} else if (z.key < y.key) {
			y.left = z;
			z.parent = y;
		} else {
			y.right = z;
			z.parent = y;
		}
	}
	
	static Node find(Tree tree, int key) {
		Node x = tree.root;
		Node y = NIL;

		while (x != NIL) {
			y = x;
			if (key == x.key) break;
			x = (key < x.key) ? x.left: x.right;
		}
		return y;
	}
	
	static void delete(Tree tree, int key){
		Node z = find(tree, key);
		if (z == NIL) return;
		
		Node y;
		if (z.left == NIL || z.right == NIL) {
			y = z;
		} else {
			for (y = z.right; y.left != NIL; y = y.left);
		}
		
		Node x = (y.left != NIL) ? y.left: y.right;
		if (x != NIL) x.parent = y.parent;
		
		if (y.parent == NIL) {
			tree.root = x;
		} else if (y == y.parent.left) {
			y.parent.left = x;
		} else {
			y.parent.right = x;
		}
		
		if (y != z) z.key = y.key;
	}

	static void preorder(Node u) {
		if (u == NIL) return;

		System.out.print(" ");
		System.out.print(u.key);
		preorder(u.left);
		preorder(u.right);
	}

	static void inorder(Node u) {
		if (u == NIL) return;

		inorder(u.left);
		System.out.print(" ");
		System.out.print(u.key);
		inorder(u.right);
	}
	
	private static byte[] buf = new byte[1 << 20];
	private static int len = 0;
	private static int ptr = 0;

	private static byte read() {
		if (ptr >= len) {
			try {
				len = System.in.read(buf);
			} catch (Exception e) {
			}
			ptr = 0;
		}

		return buf[ptr++];
	}

	private static int nextInt() {
		int num = 0;

		byte b = read();
		while(!Character.isDigit(b) && b != '-') b = read();
		int sign;
		if (b == '-') {
			sign = -1;
			b = read();
			if (!Character.isDigit(b)) return 0;
		} else {
			sign = 1;
		}
		
		while(Character.isDigit(b)) {
			num *= 10;
			num += sign * (b - '0');
			b = read();
		}
		
		return num;
	}

	private static byte[] nextbuf = new byte[11];
	private static int nextlen;

	private static void next() {
		nextlen = 0;

		byte b = read();
		while(!Character.isAlphabetic(b) && !Character.isDigit(b)) b = read();
		while(Character.isAlphabetic(b) || Character.isDigit(b)) {
			nextbuf[nextlen++] = b;
			b = read();
		}
	}
}