Analyst

You have been given a long type array/list 'arr’ of size 'n’.

It represents an elevation map wherein 'arr[i]’ denotes the elevation of the 'ith' bar.

Print the total amount of rainwater that can be trapped in these elevations.

Note :

The width of each bar is the same and is equal to 1.

Example:

Input: ‘n’ = 6, ‘arr’ = [3, 0, 0, 2, 0, 4].

Output: 10

Explanation: Refer to the image for better comprehension:

Note :

You don't need to print anything. It has already been taken care of. Just implement the given function.

Tiny URL is an online URL shortening service, where you get a short version of a given URL as a substitute.

Your task is to design encode the original URL “S”, into a tiny URL and decode the previously encoded tiny URL into the original URL.

Example:

S= “https://youtu.be/dQw4w9WgXcQ”, can be encoded to TinyUrl “http://tinyurl.com/abcdef”, then in future queries “http://tinyurl.com/abcdef”  can be decoded into “https://youtu.be/dQw4w9WgXcQ”

Note:

The URL given to you for decoding will always be one of the URLs you have already returned after encoding in the past.

The encoded URL should strictly be of the format “http://tinyurl.com/abcdef”, where instead of “abcdef” you can have any alphanumeric code of length 6.

You are given an array of 'N' integers denoting the heights of the mountains. You need to find the length of the longest subarray which has the shape of a mountain.

A mountain subarray is defined as a subarray which consists of elements that are initially in ascending order until a peak element is reached and beyond the peak element all other elements of the subarray are in decreasing order.

Example:

If the given array is: [1 3 1 4]. The longest mountain subarray would be 3. This is because the longest mountain is  [1 3 1] having length 3.

You are given an integer array 'ARR' of size 'N' and an integer 'S'. Your task is to return the list of all pairs of elements such that each sum of elements of each pair equals 'S'.

Note:

Each pair should be sorted i.e the first value should be less than or equals to the second value. 

Return the list of pairs sorted in non-decreasing order of their first value. In case if two pairs have the same first value, the pair with a smaller second value should come first.

In a database, each stored file is named by a string of size ‘N’. But due to some error in the security, some of the files got infected by a virus. Given two strings ‘A’ and ‘B’ and a virus string ‘C’, Your task is to tell the number of files that are not affected by the virus. An unaffected file follows the given conditions:

The name of the file should be greater than or equal to the string ‘A’.
The name of the file should be less than or equal to string ‘B’.
The name of the file should not contain the virus string as a substring ‘C’.
Since the answer can be very large, print answer % (10^9 + 7).

For Example

If N=2 and string ‘A’ = “bc” and string ‘B’ = “bm” and virus string ‘C’ = ”g”.So the files that are not affected are “bc”, “bd”, “be”, “bf”, “bh”, “bi”, “bj”, “bk”, “bl”.