java語言程序設(shè)計基礎(chǔ)篇第8版課后答案

1、java 語言程序設(shè)計基礎(chǔ)篇第 8 版課后答案【篇一： java 語言程序設(shè)計基礎(chǔ)篇第八章第十題編程參考答案】icequation 的類。這個類包括： 代表三個系數(shù)的私有數(shù)據(jù)域 a、b、c。 一個參數(shù)為 a、b、c 的構(gòu)造方法。 a、b、c 的三個 get 方法。一個名為 getdiscriminant() 的方法返回判別式， b2-4ac 。 一個名為getroot1() 和 getroot2() 的方法返回等式的兩個根。 這些方法只有在判別式為非負(fù)數(shù)時才有用。如果判別式為負(fù)，方法返回 0。 畫出該類的 uml 圖。實(shí)現(xiàn)這個類。編寫一個測試程序，提示用戶輸入 a、b、c 的值，然后顯示判別式

2、的結(jié)果。如果判別式為正數(shù)，顯示兩個根；如果判別式為 0，顯示一個根；否則，顯示 “the equation has noroots ”。代碼：class quadraticequation private int a,b,c;quadraticequation() public quadraticequation(int a,int b,int c) this.a=a; this.b=b; this.c=c;public int geta()return a; public int getb() return b;public int getc()return c; public int ge

3、tdiscriminant()if(b*b-4*a*c=0) return b*b-4*a*c;elsereturn 0;public int getroot1() if(b*b-4*a*c=0)return (int)(-b+math.pow(b*b-4*a*c, 0.5)/(2*a); else return 0;public int getroot2() if(b*b-4*a*c=0)else return 0;public class xiti810 public static void main(string args)system.out.println( 請輸入要計算的方程的系數(shù)

4、 a、b 和 c:);java.util.scanner input =newjava.util.scanner(system.in);system.out.print(a=);int a=input.nextint();system.out.print(b=); int b=input.nextint();system.out.print(c=); int c=input.nextint();quadraticequation q=new quadraticequation(a,b,c); q.getdiscriminant(); if(q.getdiscriminant()0)system

5、.out.println( 它們的根為： +q.getroot1()+ 和+q.getroot2(); else if(q.getdiscriminant()=0)system.out.println( 此方程只有一個根為： +q.getroot1(); elsesystem.out.println( 方程無解 );【篇二： java 語言程序設(shè)計 (第 8 版)第 5 章完整答案programming exercises( 程序練習(xí)題 )答案完整版】class exercise01 public static void main(string args) final int pentagon

6、al_numbers_per_line = 10; final int pentagonal_numbers_to_print = 100; int count = 1;int n = 1;while (count = pentagonal_numbers_to_print) int pentagonalnumber = getpentagonalnumber(n); n+;if (count % pentagonal_numbers_per_line = 0) system.out.printf(%-7dn, pentagonalnumber); elsesystem.out.printf(

7、%-7d, pentagonalnumber); count+; public static int getpentagonalnumber(int n) return n * (3 * n - 1) / 2; 5_2import java.util.scanner;public class exercise02 public static void main(string args) scanner input = new scanner(system.in); /prompt the user to enter an integersystem.out.print(enter an int

8、erger: );long number = input.nextlong(); system.out.println(the sum of the digits in + number + is +sumdigits(number); public static int sumdigits(long n) int sum = 0;long remainingn = n; do long digit = remainingn % 10; remainingn = remainingn/ 10; sum += digit; while (remainingn != 0); return sum;

9、 第 03 題import java.util.scanner;public class exercise03 public static void main(string args) scanner input = new scanner(system.in); /prompt the user to enter an integersystem.out.print(enter an integer: );int number = input.nextint(); /display result system.out.println(is + number + a palindrome? +

10、ispalindrome(number); public static boolean ispalindrome(int number) if (number = reverse(number)return true;elsereturn false; public static int reverse(int number) int reversenumber = 0;do int digit = number % 10; number = number / 10;reversenumber = reversenumber * 10 + digit; while (number != 0);

11、return reversenumber; 第 04 題import java.util.scanner;public class exercise04 public static void main(string args) scanner input = new scanner(system.in); /prompt the user to enter an integersystem.out.print(enter an integer: );int number = input.nextint();/display resultsystem.out.print(the reversal

12、 of + number + is );reverse(number); public static void reverse(int number) int reversenumber = 0;do int digit = number % 10;number = number / 10;reversenumber = reversenumber * 10 + digit; while (number != 0); system.out.println(reversenumber); 第 05 題import java.util.scanner;public class exercise05

13、 public static void main(string args) scanner input = new scanner(system.in); /prompt the user to enter three numberssystem.out.print(enter three numbers: );double num1 = input.nextdouble(); double num3 = input.nextdouble(); system.out.print(num1 + +num2 + + num3 + in increasing order: ); displaysor

14、tednumbers(num1, num2, num3); public staticvoid displaysortednumbers(double num1, double num2,double num3) double max = math.max(math.max(num1,num2), num3); double min = math.min(math.min(num1, num2),num3); double second = 0; if (num1 != max num1 !=min)second = num1; if (num2 != max num2 != min)seco

15、nd =num2; if (num3 != max num3 != min)second = num3;system.out.println(min + + second + + max); 56import java.util.scanner;public class exercise06 public static void main(string args) scanner input = new scanner(system.in); /prompt the user to enter an integersystem.out.print(enter an integer: );int

16、 number = input.nextint();displaypattern(number); public static void displaypattern(int n) int i; int j;for (i = 1; i = n; i+) for (j = 0; j n - i; j+) system.out.print( ); for (j = 0; j = i - 1; j+) system.out.printf(%-5d, i - j);system.out.println(); 5.7import java.util.scanner;public class exerci

17、se07 public static void main(string args) scanner input = new scanner(system.in); /prompt the user to enter investment amountsystem.out.print(enter the investment amount: );double investmentamount = input.nextdouble(); /prompt the user to enter interest ratesystem.out.print(enter the annual interest

18、 rate: );double annualinterestrate = input.nextdouble(); /prompt the user to enter yearssystem.out.print(enter number of years: );int years = input.nextint(); system.out.println(nthe amount invested: +investmentamount); system.out.println(annual interest rate: + annualinterestrate+ %);system.out.pri

19、ntln(yearstfuture value); for (int i = 1; i = years; i+) system.out.print(i + t); system.out.printf(%10.2fn,futureinvestmentvalue(investmentamount, annualinterestrate /1200, i); public static double futureinvestmentvalue(doubleinvestmentamount, double monthinterestrate, int years) return investmentamount * math.pow(1 + monthinterestrate,years * 12); 【篇三： java 語言程序設(shè)計基礎(chǔ)篇前三章課后習(xí)題】s=txt1.1 （顯示三條消息）編寫程序，顯示 welcome to java 、welcome to computer science 和 programming is fun 。 程序：顯示：1.2（顯示五條消息）編寫程序，顯示 welcome to