SDE - 1

You are given an array of integers. You need to sort the array in ascending order using quick sort.

Quick sort is a divide and conquer algorithm in which we choose a pivot point and partition the array into two parts i.e, left and right. The left part contains the numbers smaller than the pivot element and the right part contains the numbers larger than the pivot element. Then we recursively sort the left and right parts of the array.

Example:

Let the array = [ 4, 2, 1, 5, 3 ]
Let pivot to be the rightmost number.

After the 1st level partitioning the array will be { 2, 1, 3, 4, 5 } as 3 was the pivot. After 2nd level partitioning the array will be { 1, 2, 3, 4, 5 } as 1 was the pivot for the left part and 5 was the pivot for the right part. Now our array is sorted and there is no need to divide it again.

You have been given an Encrypted String where repetitions of substrings are represented as substring followed by the count of substrings.

Example: String "aabbbcdcdcd" will be encrypted as "a2b3cd3".

You need to find the 'K'th character of Decrypted String. Decrypted String would have 1-based indexing.

Note :

Input string will always be lowercase characters without any spaces.

If the count of a substring is 1 then also it will be followed by Integer '1'.
Example: "aabcdee" will be Encrypted as "a2bcd1e2"
This means it's guaranteed that each substring is followed by some Integer.

Also, the frequency of encrypted substring can be of more than one digit. For example, in "ab12c3", ab is repeated 12 times. No leading 0 is present in the frequency of substring.

The frequency of a repeated substring can also be in parts.
Example: "aaaabbbb" can also have "a2a2b3b1" as Encrypted String.

You are given 'N' jobs with their start time 'Start', end time 'End' and profit 'Profit'. You need to tell the maximum profit you can obtain by performing these jobs such that no two jobs overlap.

Note:

The start time of one job can be equal to the end time of another.

You have been given two arrays, 'AT' and 'DT', representing the arrival and departure times of all trains that reach a railway station.

Your task is to find the minimum number of platforms required for the railway station so that no train needs to wait.

Note :

1. Every train will depart on the same day and the departure time will always be greater than the arrival time. For example, A train with arrival time 2240 and departure time 1930 is not possible.

2. Time will be given in 24H format and colons will be omitted for convenience. For example, 9:05AM will be given as "905", or 9:10PM will be given as "2110".

3. Also, there will be no leading zeroes in the given times. For example, 12:10AM will be given as “10” and not as “0010”.

How is CPU scheduling done and what are the CPU scheduling algorithms like Round robin , SJF etc.

You are given a list of strings, ‘DICTIONARY[]’ that represents the correct spelling of words and a query string ‘QUERY’ that may have incorrect spelling. You have to check whether the spelling of the string ‘QUERY’ is correct or not. If not, then return the list of suggestions from the list ‘DICTIONARY’. Otherwise, return an empty list which will be internally interpreted as the correct string.

Note:

1) The suggested correct strings for the string  ‘QUERY’ will be all those strings present in the ‘DICTIONARY[]’ that have the prefix same as the longest prefix of string ‘QUERY’.

2) The ‘DICTIONARY[]’ contains only distinct strings.

For example:

Given 'DICTIONARY[]' = {“ninja”, “ninjas”, “nineteen”, “ninny”} and query = “ninjk”. Since “ninjk” is not present in the ‘DICTIONARY[]’, it is an incorrect string. The suggested current spellings for “ninjk” are “ninja” and “ninjas”. It is because “ninj” is the longest prefix of “ninjk” which is present as the prefix in ‘DICTIONARY’.