COSC6490A

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discussion [2007/11/02 01:07] – huiwangdiscussion [2007/11/23 13:46] (current) – franck
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-====== Slawomir's Sleeping Barber ======+===== Slawomir's Sleeping Barber =====
  
  
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-====== Sleeping Barber using Semaphore======+===== Sleeping Barber using Semaphore=====
  
 Since we have just covered semaphore in the class, here is a solution to the Sleeping Barber problem using semaphores. Althought it may looks awkward using semaphores in this problem,  Since we have just covered semaphore in the class, here is a solution to the Sleeping Barber problem using semaphores. Althought it may looks awkward using semaphores in this problem, 
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-====== Cigarette-Smokers problem ======+ 
 + 
 + 
 + 
 +===== Cigarette-Smokers problem =====
 Cigarette-Smokers problem is another famous thread synchronization problem in computer science. Cigarette-Smokers problem is another famous thread synchronization problem in computer science.
-The Cigarette-Smokers Problem. Consider a system with three smoker processes and one agent process. Each smoker continuously rolls a cigarette and then smokes it. But to roll and smoke a cigarette, the smoker needs three ingredients: tobacco, paper, and matches. One of the smoker processes has paper, another has tobacco, and the third has matches. The agent has an infinite supply of all three materials. The three smoker threads are initially blocked. The agent places two of the (different) ingredients on the table. The smoker who has the remaining ingredient then makes and smokes a cigarette, signaling+ 
 +Consider a system with three smoker processes and one agent process. Each smoker continuously rolls a cigarette and then smokes it. But to roll and smoke a cigarette, the smoker needs three ingredients: tobacco, paper, and matches. One of the smoker processes has paper, another has tobacco, and the third has matches. The agent has an infinite supply of all three materials. The three smoker threads are initially blocked. The agent places two of the (different) ingredients on the table. The smoker who has the remaining ingredient then makes and smokes a cigarette, signaling
 the agent on completion. The agent then puts out another two of the three ingredients, and the cycle repeats.  the agent on completion. The agent then puts out another two of the three ingredients, and the cycle repeats. 
  
-Given the exercieses in class, the implementation should look quite straightforward.+Given the discussions and exercises in class, the implementation should look quite straightforward.
  
 <code java> <code java>
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       Smoker smkr2 = new Smoker("S-match", table ,Table.Matches);       Smoker smkr2 = new Smoker("S-match", table ,Table.Matches);
            
-      // staring the threads+      // starting the threads
       agent.start();       agent.start();
       smkr0.start();        smkr0.start(); 
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       while (true)        while (true) 
       {       {
-         int returnValue = this.table.getAndSmoke(this.id, this.myHave);  +         int returnValue = this.table.getAndSmoke(this.id, this.myHave);  // may or may not succeed
          if ( returnValue == -100)  // read a end token, done          if ( returnValue == -100)  // read a end token, done
             break;             break;
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  }  // end of agent   }  // end of agent 
  
 +</code>
 +
 +
 +===== Franck's presentation scheduler =====
 +
 +Below you find the code that I used to schedule the third presentations.
 +
 +<code java>
 +import java.util.*;
 +import java.io.*;
 +
 +/**
 + * Prints out the schedule of the third presentations.
 + *
 + * @author Franck van Breugel
 + */
 +public class Presentation
 +{
 + /**
 +  * Prints out the schedule of the third presentations.
 +  *
 +  * @param args none.
 +  * @throws Exception if file cannot be found.
 +  */
 +  public static void main(String[] args) throws Exception
 +  {
 +    final int NUMBER_OF_STUDENTS = 16;
 +    final String FILE_NAME = "COSC6490AA";
 +    final int MAX = 1000;
 +    final int LECTURES = 4;
 +    final int NUMBER_PER_LECTURE = 4;
 +
 +    List<String> names = new ArrayList(NUMBER_OF_STUDENTS);
 +    Scanner input = new Scanner(new File(FILE_NAME));
 +    while (input.hasNext())
 +    {
 +      String[] record = input.nextLine().split(",");;
 +      names.add(record[1].trim() + " " + record[0].trim());
 +    }
 +
 +    Random random = new Random();
 +    int number = random.nextInt(MAX);
 +    for (int i = 0; i < number; i++)
 +    {
 +      Collections.shuffle(names);
 +    }
 +
 +    for (int i = 0; i < LECTURES; i++)
 +    {
 +      System.out.println("^ Slot ^ Student ^");
 +      for (int j = 0; j < NUMBER_PER_LECTURE  ; j++)
 +      {
 +        System.out.printf("| %d    | %s | %n", j + 1, names.remove(0));
 +      }
 +    }
 +  }
 +}
 </code> </code>
  
discussion.1193965672.txt.gz · Last modified: by huiwang