SDE - 1

Ninja is assigned a task to reach the last stone by his master. These stones are numbered with some value and in the form of an array. He is allowed to jump either odd-numbered jumps or even-numbered jumps and has to reach the last stone.

So your task is to find the number of starting index from which he may start jumping so he reaches the last stones. You are provided with the given array and you have to find the number of starting index of the array from which Ninja can reach the end of the array by jumping some number of times.

For jumping you have to follow below instructions:

You may jump forward from index ‘i’ to index ‘j’ (with i < j) in the following way:

During odd-numbered jumps (i.e., jumps 1, 3, 5, ...), you jump to the index ‘j’ such that ‘arr[i] <= arr[j]’ and ‘arr[j]’ is the smallest possible value. If there are multiple such indices ‘j’, you can only jump to the smallest such index j.

During even-numbered jumps (i.e., jumps 2, 4, 6, ...), you jump to the index ‘j’ such that ‘arr[i] >= arr[j]’ and ‘arr[j]’ is the largest possible value. If there are multiple such indices ‘j’, you can only jump to the smallest such index ‘j’.

It may be the case that for some index ‘i’, there are no legal jumps.

Every valid email consists of a local name and a domain name, separated by the '@' sign. Besides lowercase letters, the email may contain one or more '.' or '+'.

If you add periods '.' between some characters in the local name part of an email address, mail sent there will be forwarded to the same address without dots in the local name. Note that this rule does not apply to domain names.

If you add a plus '+' in the local name, everything after the first plus sign will be ignored. This allows certain emails to be filtered. Note that this rule does not apply to domain names.

It is possible to use both of these rules at the same time.

Given an array of 'N' strings 'emails' where we send one email to each emails[i], return the number of different addresses that actually receive mails.

For Example :

Let 'emails' = ["test.email+alex@ninjas.com", "test.e.mail+bob.case@ninjas.com", "testemail@ninjas.com"].
We need to find the number of unique email addresses after applying the rules.

The first email "test.email+alex@ninjas.com":
The local name is "test.email+alex" and the domain name is "ninjas.com".
Applying the rules to the local name:
Remove '.' -> "testemail+alex"
Ignore everything after '+' -> "testemail"
The processed email address is "testemail@ninjas.com".

The second email "test.e.mail+bob.case@ninjas.com":
The local name is "test.e.mail+bob.case" and the domain name is "ninjas.com".
Applying the rules to the local name:
Remove '.' -> "testemail+bob.case"
Ignore everything after '+' -> "testemail"
The processed email address is "testemail@ninjas.com".

The third email "testemail@ninjas.com":
The local name is "testemail" and the domain name is "ninjas.com".
No '.' or '+' in the local name.
The processed email address is "testemail@ninjas.com".

The unique processed email addresses are {"testemail@ninjas.com"}.
Therefore, the number of different addresses that actually receive mails is 1.

You are given a square matrix of non-negative integers of size 'N x N'. Your task is to rotate that array by 90 degrees in an anti-clockwise direction without using any extra space.

For example:

For given 2D array :

    [    [ 1,  2,  3 ],
         [ 4,  5,  6 ],
         [ 7,  8,  9 ]  ]

After 90 degree rotation in anti clockwise direction, it will become:

    [   [ 3,  6,  9 ],
        [ 2,  5,  8 ],
        [ 1,  4,  7 ]   ]

You are the Librarian of the Ninja library. There are ‘N’ books available in the library and ‘B’ ninjas want to read the books. You know the number of pages in each book and you have to allocate the books to the ‘B’ ninjas in such a way that the maximum number of pages allocated to a ninja is minimum.

Note

A book will be allocated to exactly one ninja. 
At least one book has to be allocated to a ninja.
Allotment of the books should be done in a contiguous manner. For example, a ninja can not be allocated book 2 and book 4, skipping book 3.

The task is to return the minimum of the maximum number of pages allocated to a ninja.