耿祥义张跃平java大学实用教程-编程题答案.doc

习题解答第一章 作业题1public class Hello public static void main (String args ) System.out.pintln(“早上好，good Morning”); 2import java.applet.*;import java.awt.*;public class Boy extends Applet public void paint(Graphics g) g.setColor(Color.blue); g.drawString(你好,hello,12,30); 第二章 作业题1public class ZuoYe2_1 public static void main (String args ) char c=; System.out.println(字母+c+在unicode表中的顺序位置:+(int)c); System.out.println(字母表：); while(c=) System.out.print( +c); c=(char)(c+1); 2import java.util.*;public class ZuoYe2_2 public static void main (String args ) Scanner reader=new Scanner(System.in); long chengji=1; int m=0; while(reader.hasNextInt() int x=reader.nextInt(); m=m+1; chengji=chengji*x; System.out.println(m+个数的乘积为+chengji); 第三章 作业题1import java.util.*;public class ZuoYe3_1 public static void main (String args ) Scanner reader=new Scanner(System.in); double y=0,x=0; x=reader.nextDouble(); if(x0) y=-1+3*x; System.out.println(y); 2public class ZuoYe3_2 public static void main(String args) int sum=0,m=3,n=7,a=1; while(a=1000) if(a%m=0&a%n=0) sum=sum+a; a+; System.out.println(sum=+sum); 3public class ZuoYe3_3 public static void main(String args) long sum=0,a=8,item=a,n=10,i=1; for(i=1;i=n;i+) sum=sum+item; item=item*10+a; System.out.println(sum); 4public class ZuoYe3_4 public static void main(String args) double sum=0,a=1,b=1,fuhao=1,item=a/b; int i=1; while(i=1000) sum=sum+fuhao*item; i+; fuhao=fuhao*(-1); b=b+2; item=a/b; System.out.println(sum=+sum); 5public class ZuoYe3_5 public static void main(String args) double sum=0,a=1; int i=1; while(i=10) sum=sum+a; i+; a=a*i; System.out.println(sum=+sum); 8第四章 作业题1class DengCha int start,d; DengCha() DengCha(int start,int d) this.start=start; this.d=d; void setStart(int s) start=s; void setD(int d) this.d=d; int getSum(int n) int sum=0,i=1; while(i=n) sum=sum+start; start=start+d; i+; return sum; public class ZuoYe4_1 public static void main (String args ) DengCha shulie=new DengCha(2,3); System.out.println(shulie.getSum(100); shulie.setStart(10); shulie.setD(5); System.out.println(shulie.getSum(9); 2 class Letter public void printLetter() for(char c=a;c=0) root1=(-b+Math.sqrt(disk)/(2*a); root2=(-b-Math.sqrt(disk)/(2*a); System.out.printf(方程的根:%f,%fn,root1,root2); else System.out.printf(方程没有实根n); else System.out.println(不是一元2次方程); public void setCoefficient(double a,double b,double c) this.a=a; this.b=b; SquareEquation.c=c; if(a!=0) boo=true; else boo=false; public class ZuoYe4_3 public static void main(String args ) SquareEquation equation1=new SquareEquation(4,5,1); SquareEquation equation2=new SquareEquation(3,5,-7); equation1.getRoots(); equation2.getRoots(); 4import java.util.Scanner;class A int f(int m,int n) if(m*n0) System.out.println(有负数，程序退出); System.exit(0); if(mn) int temp=m; m=n; n=temp; int a=m,b=n; int r=m%n; while(r!=0) m=n; n=r; r=m%n; return n; class B A a; B() a=new A(); int g(int m,int n) int temp=a.f(m,n); return m*n/temp; public class ZuoYe4_4 public static void main (String args ) Scanner reader=new Scanner(System.in); System.out.println(输入2个正整数,程序计算出它们的最大公约数和最小公倍数); System.out.print(输入第一个整数:); int m=reader.nextInt(); System.out.print(输入第二个整数:); int n=reader.nextInt(); A a=new A(); B b=new B(); System.out.println(m+和+n+的最大公约数是+a.f(m,n); System.out.println(m+和+n+的最小公倍数是+b.g(m,n); 5 import java.applet.Applet;import java.awt.*;public class Example4_10 extends Applet Button redbutton; public void init() redbutton=new Button(我是一个红色的按钮); redbutton.setBackground(Color.red);redbutton.setForeground(Color.white); add(redbutton); 第五章 作业题1import java.util.Scanner;class A public int f(int m,int n) if(mn) int temp=m; m=n; n=temp; int r=m%n; while(r!=0) m=n; n=r; r=m%n; return n; class B extends A public int f(int m,int n) int division=super.f(m,n); return (m*n)/division; public class ZuoYe5_1 public static void main (String args ) A a=new A(); B b=new B(); Scanner reader=new Scanner(System.in); System.out.println(输入2个整数,程序计算出它们的最大公约数和最小公倍数); System.out.print(输入第一个整数:); int m=reader.nextInt(); System.out.print(输入第二个整数:); int n=reader.nextInt(); if(m*n=160|age=0) throw new IntegerException(age); /方法抛出异常，导致方法结束 else this.age=age; public int getAge() System.out.println(年龄+age+合理); return age; public class ZuoYe6_5 public static void main(String args) People wang=new People(), zhang=new People(); try wang.setAge(189); System.out.println(wang.getAge(); catch(IntegerException e) System.out.println(e.toString(); try zhang.setAge(28); System.out.println(zhang.getAge(); catch(IntegerException e) System.out.println(e.toString(); 第六章 作业题1import java.util.regex.*;import java.util.*;public class ZuoYe6_1 public static void main(String args ) Scanner reader=new Scanner(System.in); String s1=reader.nextLine(); Pattern p; Matcher m; p=Ppile(24680A135792); m=p.matcher(s1); while(m.find() String str=m.group(); System.out.print(从+m.start()+到+m.end()+匹配模式子序列:); System.out.println(str); 2import java.util.regex.*;import java.util.*;public class ZuoYe4_1 public static void main(String args ) Scanner reader=new Scanner(System.in); String s1=reader.nextLine(); Pattern p; Matcher m; p=Ppile(d+); m=p.matcher(s1); while(m.find() String str=m.group(); System.out.print(str); 第七章 作业题1import java.util.*;public class ZuoYe7_2 public static void main(String args) int year,month; try year=Integer.parseInt(args0); month=Integer.parseInt(args1)+1; catch(NumberFormatException e) year=2004; month=1; System.out.println( 日 一 二 三 四 五 六); Calendar 日历=Calendar.getInstance(); 日历.set(year,month,1); int 星期几=日历.get(Calendar.DAY_OF_WEEK)-1; String a=new String星期几+31; for(int i=0;i星期几;i+) ai=*; for(int i=星期几,n=1;i星期几+31;i+) if(n=9) ai=String.valueOf(n)+ ; else ai=String.valueOf(n) ; n+; for(int i=0;ia.length;i+) if(i%7=0) System.out.println(); System.out.print( +ai); 2.class ZuoYe7_2 public static void main(String args) int year1,month1,day1,year2,month2,day2; try year1=Integer.parseInt(args0); month1=Integer.parseInt(args1); day1=Integer.parseInt(args2); year2=Integer.parseInt(args3); month2=Integer.parseInt(args4); day2=Integer.parseInt(args5); catch(NumberFormatException e) year1=2009; month1=0; day1=1; year2=2008; month2=0; day2=1; Calendar calendar=Calendar.getInstance(); calendar.set(year1,month1,day1); long timeYear1=calendar.getTimeInMillis(); calendar.set(year2,month2,day2); long timeYear2=calendar.getTimeInMillis(); long 相隔天数=Math.abs(timeYear1-timeYear2)/(1000*60*60*24); System.out.println(+year1+年+month1+月+day1+日和+ year2+年+month2+月+day2+日相隔+相隔天数+天); 3. import java.math.*;public class ZuoYe4_1 public static void main(String args) BigInteger chengji=new BigInteger(1), ONE=new BigInteger(1), i=ONE, m=new BigInteger(10); while(pareTo(m)=0) chengji=chengji.multiply(i); i=i.add(ONE); System.out.println(chengji); 4import java.util.*;public class ZuoYe7_4 public static void main(String args) HashSet A=new HashSet(), B=new HashSet(), tempSet=new HashSet(); A.add(new Integer(1); A.add(new Integer(2); A.add(new Integer(3); A.add(new Integer(4); B.add(new Integer(1); B.add(new Integer(3); B.add(new Integer(7); B.add(new Integer(9); B.add(new Integer(11); tempSet=(HashSet)A.clone(); tempSet.retainAll(B); System.out.println(交：); Iterator iter=tempSet.iterator(); while(iter.hasNext() Integer te=iter.next(); System.out.printf(%d，,Value(); tempSet=(HashSet)A.clone(); tempSet.addAll(B); iter=tempSet.iterator(); System.out.println(并：); while(iter.hasNext() Integer te=iter.next(); System.out.printf(%d，,Value(); tempSet=(HashSet)A.clone(); tempSet.removeAll(B); System.out.println(差：); iter=tempSet.iterator(); while(iter.hasNext() Integer te=iter.next(); System.out.printf(%d，,Value(); 5import java.util.*;class MyKey implements Comparable double number=0; MyKey(double number) this.number=number; public int compareTo(Object b) MyKey st=(MyKey)b; if(this.number-st.number)=0) return -1; else return (int)(this.number-st.number)*1000); class 硬盘 int size; double price; 硬盘(int n, double p) size=n; price=p; public class ZuoYe4_1 public static void main(String args ) int size=10,3,7,12,10,22,100,4,6,2; double price=1.2,9.56,2.4,9.3,16.77,12.66,7.4,5.5,5.6,8.9,1.9; 硬盘 s=new 硬盘10; for(int i=0;is.length;i+) si=new 硬盘(sizei,pricei); TreeMap treemap=new TreeMap(); for(int i=0;is.length;i+) treemap.put(new MyKey(si.size),si); int number=treemap.size(); System.out.println(树映射中有+number+个对象:); Collection collection=treemap.values(); Iterator iter=collection.iterator(); while(iter.hasNext() 硬盘 te=iter.next(); System.out.println(te.size+,+te.price); treemap.clear(); for(int i=0;is.length;i+) treemap.put(new MyKey(si.price),si); number=treemap.size(); System.out.println(树映射中有+number+个对象:); collection=treemap.values(); iter=collection.iterator(); while(iter.hasNext() 硬盘 te=iter.next(); System.out.println(te.size+,+te.price); 第八章 作业题1属于操作题目，省略2参见例子8-23参见例子8-34. 参见例子8-10第九章 作业题1impor