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public class ExOperator1 {
  public static void main(String[] args) {
    int x = 10;
    int y = 10;

    //ÊÑ¿ôx¤ÎÃͤò1Áý²Ã¤µ¤»¤¿¸å¡¢ÊÑ¿ôanswerX¤ËÂåÆþ¤ò¹Ô¤¦¡£
    int answerX = ++x;   //­¡

    //ÊÑ¿ôy¤òÊÑ¿ôanswerY¤ËÂåÆþ¤·¤¿¸å¡¢ÊÑ¿ôy¤ÎÃͤò1Áý²Ã¤µ¤»¤ë¡£
    int answerY = y++;   //­¢

    System.out.println(answerX + " : " + x);   //­£
    System.out.println(answerY + " : " + y);   //­¤
  }
}
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D:\JAVA>javac ExOperator1.java

D:\JAVA>java ExOperator1
11 : 11
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D:\JAVA>

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public class ExOperator2 {
  public static void main(String[] args) {
    int a1 = 10;
    double b1 = 20.05;
    int c1 = a1 + b1;   //­¡

    int a2 = 10;
    long b2 = 1000;
    int c2 = a2 + b2;   //­¢

    byte a3 = 10;
    byte b3 = 10;
    byte c3 = a3 + b3;   //­£
  }
}
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D:\JAVA>javac ExOperator2.java
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¡¡¡¡ int c1 = a1 + b1;
¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡ ^

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¡¡¡¡ int c2 = a2 + b2;
¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡ ^

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¡¡¡¡ byte c3 = a3 + b3;
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public class ExOperator3 {
  public static void main(String[] args) {
    double exOperand = 123.45;   //(1)
    System.out.println("Åú¤¨¤Ï" + "123.45");   //(2)
    System.out.println("Åú¤¨¤Ï" + exOperand);   //(3)
  }
}
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D:\JAVA>javac ExOperator3.java

D:\JAVA>java ExOperator3
Åú¤¨¤Ï123.45
Åú¤¨¤Ï123.45

D:\JAVA>



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