How to generate random numbers with no repeat javascript

Question

I am using the following code which generates random number between 0 to Totalfriends, I would like to get the random numbers but they should not be repeated. Any idea how?<

Answer 1

1. create an array (e.g. yourarray) of numbers in range [1..totalfriends]
2. shuffle the array (e.g. using a javascript implementation of Fisher-Yates algorithm)
3. inside the for (from 0 to yourarray.length - 1) make a pop() from the array (or just get the n-th element) so you will get everytime a different number

Doing so you you will avoid to get duplicated numbers