Time Limit : sec, Memory Limit : KB
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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:

  1. If $z$ has no children, we modify its parent $z.p$ to replace $z$ with NIL as its child (delete $z$).
  2. If $z$ has only a single child, we "splice out" $z$ by making a new link between its child and its parent.
  3. If $z$ has two children, we splice out $z$'s successor $y$ and replace $z$'s key with $y$'s key.


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.


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


  • 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

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
delete 3
delete 7

Sample Output 1

 1 2 3 7 8 22
 8 2 1 3 7 22
 1 2 8 22
 8 2 1 22


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