Help with random numbers no repeats

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1

Hi im trying to have random numbers from 1 to 90 how would i do it so numbers do not repeat,
here is the code i have

var num:Number = Math.ceil(Math.random()*90);
2

Fill an array with numbers from 1-90, then select a random element and then use splice to remove it from the array.

3

I think best way is to use timestamp.

4

How and why do you think using TimeStamp is better than EastCoast’s way?

5

I think was wrong for this solution.
EastCoast is right, the way I suggested is only a unique no which never repeats.
but it doesn’t lies in between 1 to 90.