Challenge

Question

Write a program to find the permutation of n , not all different things taking r at a time.
Like , find the permutation with digits 7,6,7,8,9,8 taking 3 at a time.
This question is not as easy as it seems, if it is asked taking all at a time (like, if there are 8, not all different things & we have to find permutation taking 8 at a time) then ,this becomes very easy(n!/(a!*b!....)) but here , this is not the case.

Sample Input - 97897
3
Sample Output- Permutation of 97897 taking 3 at a time = 18

Answer 1

Sorry, I have not seen before.
Thank you for the invitation. Here's my try :

https://code.sololearn.com/cr202esYb0S5/?ref=app

Answer 2

RAHUL JAISWAL
I tried to explain my approach in the comment section of my code 😉

Answer 3

here is my attempt in python:

https://code.sololearn.com/cLHCALs9bvwZ/?ref=app

Answer 4

LukArToDo , Awesome frnd 🤞
It's my pleasure 😊,
please share your Mathematical approach of doing this, I am just a Beginner in Kotlin.