The Dining Philosophers (cont.)

Array [1..5] of semaphores : fork = [1, 1, 1, 1, 1 ];

semaphore : table = 4;

Philosopher Pi:

Repeat

think;

wait( table ); wait( fork[i] );

wait( fork[ (i+1) mod 5 );

eat;

signal( fork[ (i+1) mod 5 );

signal( fork[i] ); signal( table );

Forever

Allow only 4 of them to come to the table at the same time

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