On 16/11/2011 11:47 AM, Jeremy Gibbons wrote:

On 15 Nov 2011, at 13:03, Robert Dawson wrote:

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My recollection was that there were two versions - "dining philosophers" who had shared access to two forks, either one of which sufficed; and "dining Chinese philosophers" who had shared access to two chopsticks of which both were needed.

The dining philosophers need both forks/chopsticks. The point of the problem is the competing access to shared resources: how to manage the requests to avoid deadlock (eg by everyone picking up their left fork, and then blocking on waiting for the right fork).

It seems to me there was a single fork version too in which the (intentionally less difficult) problem occurred when the two neighbours of one philosopher picked up both the forks to which he had access; and that the point of the chopsticks was to make one implement useless. Robert [For admin and other information see: http://www.mta.ca/~cat-dist/ ]