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本题分别比较两个字符串"A"和"a"是否相等,并比较两个字符"A"和"a"是否相等,并输出比较结果。

public class javal{

public static void main(String[]args){

____;

cl=‘A ‘;c2=‘a‘;

String strl=new String("A"),str2=new String

("a"):

if(____)

System.Out.println("char"+c1+"equals"+"char"

+c2);

else

System.OUt.println("char"+cl+"doesn‘t equal

"+"char"+c2);

if(____)

System.out.println("string"+strl+"equals"+

"string"+str2):

else

System.OUt.println("string"+strl+"doesn‘t e-

qual"+"string"+str2); .

}

}

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    return C;

    }

    public void____{

    int m=(bold.isSelected()?Font.BOLD:O)+

    (italic.isSelected()?Font.ITALIC:O);

    panel.setFont(m);

    }

    private CheckBoxTestPanel panel;

    private JCheckBox bold;

    private JCheckBox italic;

    }

    class CheckBoxTestPanel extends JPanel{

    public CheckBoxTestPanel(){

    setFont(Font.PLAIN);

    }

    public void setFont(int m){

    setFont(new Font("SansSerif",m,12));

    repaint();

    }

    public void paintComponent(Graphics g){

    super.paintComponent(g);

    9.drawstring("The quick brown fox jumps over

    the lazy dog.",0,50);

    }

    }

    public class java2{

    public static void main(String[]args){

    JFrame. frame=new CheckBoxFrame();

    frame.show();

    }

    }

  10. 本题统计score[]={37,89,63,60,59,78,91)中成绩不及格的人数。

    public class javal{

    public static void main(String[]args){

    int score[]={37,89,63,60,59,78,91),

    int sum=0:

    int i=0;

    while(i<;score.length){

    if(score[i]>;=60){

    ____;

    ____;

    }

    ____;

    i++;

    }

    System.OUt.println("below 60 sum:"+sum);

    }

    }