System Engineer

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.

A buyer buys X kg apples at total Y Rs. If he sells K kg of the apples at P% profit, what is the total profit amount he made.
Input-
X = 5
Y = 50
K = 3
P = 20

I wrote the program which ran the loop N times, and then later realised the for loop was required to run till sqrt(N) times only, the interviewer did ask me for an optimised solution, but I couldn't give it, so he moved on to next question

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