华工java语言程序设计作业答案18章

1、华南理工大学学生实验报告书实验名称java课程实验课程名称Java语言程序设计 课王 号 学院软件学院专业 软件工程 班级 学生姓名*学号 *实验地点实验日期第一早1.3public class Exe1_3public static void main( Stri ng args)System.out.pri ntl n(JA V V ASystem.out.pri ntl n(JA A V V A ASystem.out.pri ntl n(J JAAAAA V V AAAAASystem.out.pri ntl n(J JA A V A A););););1 A V V AJ A A V

2、 V A AJ AMAA V V AAMA3 1 A A V A A2.21import java.util.Sca nner;public class Exe2_21public static void main( Stri ng args);System. out .println(Enter three points for triangle :Scanner in put =new Scann er(System. in );double x1 = in put .n extDouble(); double y1 = in put .n extDouble();double x2 =

3、in put .n extDouble(); double y2 = in put .n extDouble(); double x3 = in put .n extDouble(); double y3 = in put .n extDouble();doubleside1=Math. sqrt (x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);doubleside2=Math. sqrt (x1-x3)*(x1-x3)+(y1-y3)*(y1-y3);doubleside3=Math. sqrt (x2-x3)*(x2-x3)+(y2-y3)*(y2-y3);double s

4、 = (sidel + side2 + side3) / 2;double area = Math. sqrt ( s * (s-side1) * (s-side2) (s-side3);System. out .println(The area of the triangle is + area);Enter three points for triangle :1.5 -3-4 4.6 5 9.5|lh area af tiie triangle is S3.第三章3.27importjava.util.Sca nner;public class Exe3_27finaldoublex1

5、= 0;finaldoubley1 = 0;finaldoublex2 200;finaldoubley2 = 0;finaldoublex3 = 0;finaldoubley3 = 100;public static void main( Stri ng args)Scanner in put =new Scann er(System.in ););System. out .println(Entera pointsx- and y-coordinatesdouble x = in put. nextDouble();double y = in put. nextDouble(); doub

6、le y_x = -(x/2) + 100;if ( xx1 & xy_x )System. out .println(elseSystem. out .println(The pointThe pointThe pointis not in the triangle!is not in the triangle!is not in the triangle!The point is in the triangle!）；）；）；）；Enter a point呂 x- and y-coordinates :IS.5 25.5The point is in the triangle I3.29 i

7、mport java.util.Sca nner;public class Exe3_29public static void main( Stri ng args)Scanner in put =new Scann er(System. in );cen terSystem. out .println(Entercirclelsx- ,y-coord in ates and radius :);double x1 = in put. nextDouble();double y1 = in put. nextDouble();double r1 = in put. nextDouble();c

8、en terSystem. out .println(Entercircle2sx- ,y-coord in ates and radius :);double x2 = in put .n extDouble(); double y2 = in put .n extDouble(); double r2 = in put. nextDouble();double(y1-y2)*(y1-y2);doublelen gthMath. sqrt (x1-x2)*(x1-x2)doubleL1 = Math. abs ( r1 - r2 );L2 = r1 + r2;if (length = L1)

9、System. out .println(else if (length = L2)System. out .println(elseSystem. out .println(circle2 is in circle);circle2 overlaps circle);circle2 does not overlap circle1);Enter circlel center x&. 5 5 .1 13Enter circled 1e center m-1 1.7 4_5circle2 is in circlel!jy-c-ocrdinatcs and radium ; t y-c-oordi

10、nates and rmdium :第四章4.25public class Exe4_25public static void main( Stri ng args) double PI = 0,sum = 0;int i, n;for ( i = 10000; i = 100000; i += 10000 ) for ( n = 1; n i; n += 2 ) sum += (1.0/(2*n-1) - 1.0/(2*n+1);PI = 4 * sum;System. out .println( sum = 0;II;I!and 兀=+ PI );i = 10&0 and * 3.1414

11、9265359&0367i - 2&Q and 二二 3.1415426535S9S203i = 300&0 and 7T 346841 =哪辭 and -= 3.X1557S535357927|l = 500&S ard -= 3 max)max = in teger; count = 1;else if (integer max)elsecoun t+=1;；System.out .println(The largest nu mber is + max);System.out .println(The occure neecountof the largestn

12、u mber is +cou nt);Enter numbers :5 52 5 5 BThe largest number is $The occurence count o-f the Largest number is 4第五章5.21importjava.util.Sca nner;in ););public class Exe5_21public static voidScanner in put = double ary =System. out .println(main( Stri ng args)new Scann er(System. new double 10;En te

13、r ten nu mbers :for ( int i = 0; i ary.aryi = in put. nextDouble();len gth; i+ )double sum = 0, sum_pow = 0; for (int i = 0; i ary.sum += aryi;for (int i = 0; i ary.sum_pow += aryi*aryi;len gth; i+)len gth; i+)doubledouble sum*sum/ary.mea n = sum/ary. len gthsta ndard_valuelen gth ) / (ary.len gth1.

14、0);Math. sqrt (sum_powSystem. out .println(Thesta ndarddeviati onissta ndard_value); Enter ten numbers ;1 234.66785 10The mean is 5.61The standard dewiation is 2.957343739743494第六章6.18import java.util.Sca nner;public class Exe6_18 public static voidmain (Stri ng args)En ter ten real nu mber : new do

15、uble 10;）；System. out .print( double array = In put (array);Sort (array);Output (array);/public static void输入In put( double ary)Scanner in put =(int i = 0; i ary. aryi = in put. nextDouble();fornew Scanner(System. in );i+)len gth/ public输出static void Output(doubleary)for(int i = 0; i ary. System. ou

16、t .print(I!I!len gth+;i+) aryi);冒泡排序static void Sort(/ publicdouble ary)for(int i =1; i ary.len gth;i+)work =true ;for ( n =:0; n aryn+1) temp = ary n; aryn = aryn+1;aryn+1 = temp; work = falseif (work) break ;Enter ten real number : 1 J. 一： r. ： 4 2 123 6 2LJ 55+ 2126.45.064.0123.0213.0第七章7.6 impor

17、tjava.util.Sca nner;class Exe7_6finalstaticfinalstaticpublicpublicstaticintR = 3;intL = 3;void main( Stri ngargs)double matrix1 =new double L R;System. out .println(Enter matrix1 :);double matrix2 = new double L R;In put (matrix1);System. out .println(In put (matrix2);En ter matrix2 :）；Output (matri

18、x1,matrix2,multiplyMatrix (matrix1,matrix2);/输入public static void In put( double matrix) Scanner in put =new Sea nn er(System.in );for ( int line = 0; line L; line+)for ( int row = 0; row R; row+)matrixli nerow = in put. nextDouble();/输出public staticb, double matrix)int n = 0;for (int i = 0; i if (

19、i != 1)for ( n = 0; n System.System.void Output( double L; i+ )R; n+)a, double for ( n = 0; n System.System.out .print(out .print( R; n+) out .print( for ( n = 0; n System. elsefor ( n = 0; n System.System.out .print( R; n+) out .print( + ai n););+ bi n););+ matrixi n);for ( n = 0; n System.System.R

20、; n+) out .print(out .print( *R; n+) out .print(+ ai n ););+ bi n ););out .print(for ( n = 0; n R; n+)System. out .print(+ matrixi n);System. out .println();multiplyMatrix(double a,double b) double c =new double L R;for ( int i = 0;i L; i+)/矩阵相乘public static double for ( intj = 0; j R; j+)cij = 0;fo

21、r (int k = 0; k 1.08.13import java.util.Sca nner;public class Exe8_13public static void main( Stri ng args)Scanner in put =new Sca nn er(System.in );System. out .println(Enter the number of rows and columns ofthe array :);int row = in put. nextl nt();int colu mn = in put. next In t();double array =new double rowcolumn;);System. out .println( Enter the array : for (int i = 0; i row; i+)for (int n = 0; n column;