アルゴリズム編-奇数偶数を交互に印刷

13209 ワード

アルゴリズム

タイトル
奇数を交互に印刷

リソースエンティティ

public class Num {

    int i = 1;

    // true:        false:     
    boolean flag = true;

}

奇数スレッドの印刷

public class PrintOddThread implements Runnable {
    private final Num num;

    public PrintOddThread(Num num) {
        this.num = num;
    }

    @Override
    public void run() {
        while (num.i < 10000) {
            synchronized (num) {
                if (num.flag) {
                    System.out.println("  \t" + num.i);
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    num.i++;
                    num.flag = false;
                } else {
                    try {
                        num.wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    }
}

偶数スレッドの印刷

public class PrintEvenThread implements Runnable {
    private final Num num;

    public PrintEvenThread(Num num) {
        this.num = num;
    }

    @Override
    public void run() {
        while (num.i < 10000) {
            synchronized (num) {
                if (!num.flag) {
                    System.out.println("  \t" + num.i);
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    num.i++;
                    num.flag = true;
                } else {
                    num.notify();
                }
            }
        }
    }
}

しゅかんすう

public class App {

    public static void main(String[] args) throws IOException {

        ExecutorService executor = Executors.newFixedThreadPool(2);

        Num num = new Num();

        executor.execute(new PrintOddThread(num));
        executor.execute(new PrintEvenThread(num));
		
		executor.shutdown();
    }

}

実行結果

Petersonアルゴリズムの理解

python+selenium学習レコード