| # | Problem | Pass Rate (passed user / total user) |
|---|---|---|
| 1005 | How Many Trees? |
|
| 1006 | The Disks |
|
Description
A binary search tree is a binary tree with root k such that any node v in the left subtree of k has label (v) <label (k) and any node w in the right subtree of k has label (w) > label (k).
When using binary search trees, one can easily look for a node with a given label x: After we compare x to the label of the root, either we found the node we seek or we know which subtree it is in. For most binary search trees the average time to find one of its n nodes in this way is O(log n).
Given a number n, can you tell how many different binary search trees may be constructed with a set of numbers of size n such that each element of the set will be associated to the label of exactly one node in a binary search tree?
Input
The input will contain a number 1 <= i <= 1000 per line representing the number of elements of the set.
Output
You have to print a line in the output for each entry with the answer mod 32767 to the previous question.
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Description
For his birthday present little Johnny has recieved from his parents a new plaything which consists of a tube and a set of disks. The aforementioned tube is of unusual shape. Namely, it is made of a certain number of cylinders (of equal height) with apertures of different diameters carved coaxially through them. The tube is closed at the bottom, open at the top. An exemplary tube consisting of cylinders whose apertures have the diameters: 5cm, 6cm, 4cm, 3cm, 6cm, 2cm and 3cm is presented in the image bellow.

The disks in Johnny's plaything are cylinders of different diameters and height equal to those forming the tube.
Johnny has invented a following game: having a certain set of disks at his disposal, he seeks to find what depth the last of them would stop at, assuming that they are being thrown into the centre of the tube. If, for instance, we were to throw disks of consecutive diamaters: 3cm, 2cm and 5cm, we would obtain the following situation:

As you can see, upon being thrown in, every disk falls until it gets stuck (which means that it lies atop a cylinder, aperture of which has a diameter smaller than the diameter of the disk) or it is stopped by an obstacle: the bottom of the tube or another disk, which has already stopped.
The game being difficult, Johnny constantly asks his parents for help. As Johnny's parents do not like such intelectual games, they have asked you - an acquaintance of theirs and a programmer - to write a programme which will provide them with answers to Johnny's questions.
Write a programme which:
- reads the description of the tube and the disks which Johnny will throw into it from the standard input,
- computes the depth which the last disk thrown by Johnny stops at,
- writes the outcome to the standard output.
Input
The first line of the standard input contains two integers n and m ( 1
n, m
300 000) separated by a single space and denoting the height of Johnny's tube (the number of cylinders it comprises) and the number of disks Johnny intends to throw into it, respectively. The second line of the standard input contains n integers r1, r2,...,rn ( 1
ri
1 000 000 000 for 1
i
n) separated by single spaces and denoting the diameters of the apertures carved through the consecutive cylinders (in top-down order), which the tube consists of. The third line contains m integers k1, k2,..., km ( 1
kj
1 000 000 000 for 1
j
m) separated by single spaces and denoting the diameters of consecutive disks which Johnny intends to throw into the tube.
Output
The first and only line of the standard output should contain a single integer denoting the depth which the last disk stops at. Should the disk not fall into the tube at all, the answer should be 0.