SDE - Intern

You are given a string 'STR' containing lowercase English letters from a to z inclusive. Your task is to find all non-empty possible subsequences of 'STR'.

A Subsequence of a string is the one which is generated by deleting 0 or more letters from the string and keeping the rest of the letters in the same order.

A permutation is a mathematical technique that determines the number of possible arrangements in a set when the order of the arrangements matters. A string of length 'N' has 'N'! permutations.

Given an array of distinct integers, return all the possible permutations of the array.

Example:

'ARR[]' = [1, 2]

The size of the array is 2. So, the total number of permutations is 2! = 2. The possible permutations are [1, 2] (the array itself) and [2,1] where the position of element 1 in the original array is swapped with element 2 and vice-versa.   

Note:

1. All the numbers in the array are unique.

2. You can return the answer in any order.

3. The original array is also a permutation of the given array.

You are given an array consisting of 'N' distinct positive integers and a number 'K'. Your task is to find the kth largest element in the array.

Example:

Consider the array {2,1,5,6,3,8} and 'K' = 3, the sorted array will be {8, 6, 5, 3, 2, 1}, and the 3rd largest element will be 5.

Note:

1) Kth largest element in an array is the kth element of the array when sorted in non-increasing order. 

2) All the elements of the array are pairwise distinct.

You are given an integer array 'A' of size 'N', sorted in non-decreasing order. You are also given an integer 'target'. Your task is to write a function to search for 'target' in the array 'A'. If it exists, return its index in 0-based indexing. If 'target' is not present in the array 'A', return -1.

Note:

You must write an algorithm whose time complexity is O(LogN)

You have been given a sorted array/list 'arr' consisting of ‘n’ elements. You are also given an integer ‘k’.

Now the array is rotated at some pivot point unknown to you.

For example, if 'arr' = [ 1, 3, 5, 7, 8], then after rotating 'arr' at index 3, the array will be 'arr' = [7, 8, 1, 3, 5].

Now, your task is to find the index at which ‘k’ is present in 'arr'.

Note :

1. If ‘k’ is not present in 'arr', then print -1.
2. There are no duplicate elements present in 'arr'. 
3. 'arr' can be rotated only in the right direction.

Example:

Input: 'arr' = [12, 15, 18, 2, 4] , 'k' = 2

Output: 3

Explanation:
If 'arr' = [12, 15, 18, 2, 4] and 'k' = 2, then the position at which 'k' is present in the array is 3 (0-indexed).