To my shame I must confess I used the same algorithm with my mp3 player. And I didn't give a thought about efficiency.

If you do mind, you could just sum up the all the weights and do the looking up on a second walkthrough. Definitely more memory efficient and if your weights are above 2 on average it would be faster too.

You could also keep a running weight total that would be updated on every addition or deletion in the group.

In reply to Re: Weighted random selection by jethro
in thread Weighted random selection by cosmicperl

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