Java程序设计习题集
public class Applet1 extends Applet { }
答：
10．import java.io.*; public class abc
{ public static void main(String args[]) { SubClass sb = new SubClass( ); System.out.println(sb.max( )); } }
class SuperClass
{ int a = 10 , b = 20 ; }
class SubClass extends SuperClass
{ int max( ) { return ((a>b)?a:b); } } 答：
public void paint( Graphics g ) { }
g.drawLine( 30,5,100,45 ); g.drawRect( 30,50,50,20 ); g.drawOval( 30,80,50,40 );
g.drawString( \
五、写出下面程序的运行结果
1．import java.io.*;
public class abc
{ public static void main(String args[ ]) { AB s = new AB(\ System.out.println(s.toString( )); } }
class AB {
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Java程序设计习题集
String s1; String s2;
AB( String str1 , String str2 ) { s1 = str1; s2 = str2; } public String toString( ) { return s1+s2;} } 答：
2．import java.io.* ; public class abc {
public static void main(String args[ ]) { int i , s = 0 ;
int a[ ] = { 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 };
for ( i = 0 ; i < a.length ; i ++ ) if ( a[i]%3 = = 0 ) s += a[i] ; System.out.println(\ } }
答：s =
3． import java.io.* ; public class abc {
public static void main(String args[ ]) { SubSubClass x = new SubSubClass(10 , 20 , 30); x.show(); } }
class SuperClass
{ int a,b;
SuperClass(int aa , int bb) { a=aa; b=bb; }
void show( )
{ System.out.println(\ }
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Java程序设计习题集
class SubClass extends SuperClass { int c;
SubClass(int aa,int bb,int cc) { super(aa,bb); c=cc; } }
class SubSubClass extends SubClass { int a;
SubSubClass(int aa,int bb,int cc) { super(aa,bb,cc); a=aa+bb+cc;
}
void show()
{ System.out.println(\ } 答：a= b= c=
4． import java.io.*;
public class abc {
public static void main(String args[]) {
String s1 = \
String s2 = new String(\ System.out.println(s1.concat(s2)); }
}
答：Hello!World!
5． import java.io.* ; public class ABC {
public static void main(String args[ ]) { int i ;
int a[ ] = { 11,22,33,44,55,66,77,88,99 };
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Java程序设计习题集
for ( i = 0 ; i <= a.length / 2 ; i ++ )
System.out.print( a[i]+a[a.length-i-1]+\ }
System.out.println( );
}
答：110 110 110 110
6． import java.io.*; class Parent { } { }
public class Class1 {
public static void main(String args[ ]) {
Child myC = new Child( ); }
myC.printAll( ); }
void printMe() { }
System.out.println(\
class Child extends Parent
}
void printMe() { System.out.println(\}
void printAll() { super.printMe(); this.printMe(); printMe();
答：
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