java语言程序设计基础篇第十版第十三章练习标准答案

java语言程序设计基础篇第十版第十三章练习答案BigIntegergcd=gcd(numerator,denominator);if(pareTo(Biglnteger.ZERO)<0)this.numerator=numerator.multiply(newBigInteger("-1")).divide(gcd);elsethis.numerator=numerator.divide(gcd);this.denominator=denominator.abs().divide(gcd);}/**FindGCDoftwonumbers*/privatestaticBigIntegergcd(BigIntegern,BigIntegerd){BigIntegern1=n.abs();BigIntegern2=d.abs();BigIntegergcd=BigInteger.ONE;for(BigIntegerk=BigInteger.ONE;pareTo(nl)<=0&&pareTo(n2)<=0;k=k.add(BigInteger.ONE)){if(nl.remainder(k).equals(BigInteger.ZERO)&&n2.remainder(k).equals(BigInteger.ZERO))gcd=k;}returngcd;}/**Returnnumerator*/publicBigIntegergetNumerator(){returnnumerator;}/**Returndenominator*/publicBigIntegergetDenominator(){returndenominator;}/**Addarationalnumbertothisrational*/publicRationaladd(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getDenominator()).add(denominator.multiply(secondRational.getNumerator()));BigIntegerd=denominator.multiply(secondRational.getDenominator());returnnewRational(n,d);}

/**Subtractarationalnumberfromthisrational*/publicRationalsubtract(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getDenominator()).subtract(denominator.multiply(secondRational.getNumerator()));BigIntegerd=denominator.multiply(secondRational.getDenominator());returnnewRational(n,d);}/**Multiplyarationalnumbertothisrational*/publicRationalmultiply(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getNumerator());BigIntegerd=denominator.multiply(secondRational.getDenominator());returnnewRational(n,d);}/**Dividearationalnumberfromthisrational*/publicRationaldivide(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getDenominator());BigIntegerd=denominator.multiply(secondRational.numerator);returnnewRational(n,d);}@OverridepublicStringtoString(){if(denominator.equals(BigInteger.ONE))returnnumerator+"";elsereturnnumerator+"/"+denominator;}@Override/**OverridetheequalsmethodintheObjectclass*/publicbooleanequals(Objectparml){if((this.subtract((Rational)(parm1))).getNumerator().equals(BigInteger.ONE))returntrue;elsereturnfalse;}@Override/**OverridethehashCodemethodintheObjectclass*/publicinthashCode(){returnnewDouble(this.doubleValue()).hashCode();}@Override/**OverridetheabstractintValuemethodinjava.lang.Number*/

publicintintValue(){return(int)doubleValue();}@Override/**OverridetheabstractfloatValuemethodinjava.lang.Number*/publicfloatfloatValue(){return(float)doubleValue();}@Override/**OverridethedoubleValuemethodinjava.lang.Number*/publicdoubledoubleValue(){returnnumerator.doubleValue()/denominator.doubleValue();}@Override/**OverridetheabstractlongValuemethodinjava.lang.Number*/publiclonglongValue(){return(long)doubleValue();}@OverridepublicintcompareTo(Rationalo){if((this.subtract((Rational)o)).getNumerator().compareTo(BigInteger.ZERO)>0)return1;elseif((this.subtract((Rational)o)).getNumerator().compareTo(BigInteger.ZERO)<0)return-1;elsereturn0;}}}16publicclassExercise13_16{publicstaticvoidmain(String口args){Rationalresult=newRational。1);if(args.length!=1){System.out.println("Usage:javaExercise13_16\"operand1operatoroperand2\"");System.exit(1);}String[]tokens=args[0].split("");

switch(tokens[1].charAt(0)){case'+':result=getRational(tokens[0]).add(getRational(tokens[2]));break;case'-':result=getRational(tokens[0]).subtract(getRational(tokens[2]));break;case'*':result=getRational(tokens[0]).multiply(getRational(tokens[2]));break;case'/':result=getRational(tokens[0]).divide(getRational(tokens[2]));}System.out.println(tokens[0]+""+tokens[1]+""+tokens[2]+"="+result);}staticRationalgetRational(Strings){String口st=s.split("/");intnumer=Integer.parseInt(st[0]);intdenom=Integer.parseInt(st[1]);returnnewRational(numer,denom);}}/*Alternatively,youcanuseStringTokenizer.SeeSupplementIII.AAonStringTokenizerasalternativeimportjava.util.StringTokenizer;publicclassExercise15_18{publicstaticvoidmain(String口args){Rationalresult=newRational。1);if(args.length!=3){System.out.println("Usage:javaExercise15_22operand1operatoroperand2");System.exit(0);}switch(tokens[1].charAt(0)){case'+':result=getRational(tokens[0]).add(getRational(tokens[2]));break;case'-':result=getRational(tokens[0]).subtract(getRational(tokens[2]));break;case'*':result=getRational(tokens[0]).multiply(getRational(tokens[2]));break;case'/':result=getRational(tokens[0]).divide(getRational(tokens[2]));

System.out.println(tokens[0]+""+tokens[1]+""+tokens[2]+"="+result);}staticRationalgetRational(Strings){StringTokenizerst=newStringTokenizer(s,"/");intnumer=newInteger(st.nextToken()).intValue();intdenom=newInteger(st.nextToken()).intValue();returnnewRational(numer,denom);}}*/17importjava.util.Scanner;publicclassExercise13_17{publicstaticvoidmain(String口args){Scannerinput=newScanner(System.in);System.out.print("Enterthefirstcomplexnumber:");doublea=input.nextDouble();doubleb=input.nextDouble();Complexc1=newComplex(a,b);System.out.print("Enterthesecondcomplexnumber:");doublec=input.nextDouble();doubled=input.nextDouble();Complexc2=newComplex(c,d);System.out.println("("+c1+")"+"+"+"("+c2+")"+"="+c1.add(c2));System.out.println("("+c1+")"+"-"+"("+c2+")"+"="+c1.subtract(c2));System.out.println("("+c1+")"+"*"+"("+c2+")"+"="+c1.multiply(c2));System.out.println("("+cl+")"+"/"+"("+c2+")"+"="+c1.divide(c2));System.out.println("|"+cl+"|="+c1.abs());Complexc3=(Complex)c1.clone();System.out.println(c1==c3);System.out.println(c3.getRealPart());System.out.println(c3.getImaginaryPart());}}classCompleximplementsCloneable{privatedoublea=0,b=0;

publicComplex。{}Complex(doublea,doubleb){this.a=a;this.b=b;}publicComplex(doublea){this.a=a;}publicdoublegetA(){returna;}publicdoublegetB(){returnb;}publicComplexadd(ComplexsecondComplex){doublenewA=a+secondComplex.getA();doublenewB=b+secondComplex.getB();returnnewComplex(newA,newB);}publicComplexsubtract(ComplexsecondComplex){doublenewA=a-secondComplex.getA();doublenewB=b-secondComplex.getB();returnnewComplex(newA,newB);}publicComplexmultiply(ComplexsecondComplex){doublenewA=a*secondComplex.getA()-b*secondComplex.getB();doublenewB=b*secondComplex.getA()+a*secondComplex.getB();returnnewComplex(newA,newB);}publicComplexdivide(ComplexsecondComplex){doublenewA=(a*secondComplex.getA()+b*secondComplex.getB())/(Math.pow(secondComplex.getA(),2.0)+Math.pow(secondComplex.getB(),2.0));doublenewB=(b*secondComplex.getA()-a*secondComplex.getB())

/(Math.pow(secondComplex.getA(),2.0)+Math.pow(secondComplex.getB(),2.0))；returnnewComplex(newA,newB);}publicdoubleabs(){returnMath.sqrt(a*a+b*b);}@OverridepublicStringtoString(){if(b!=0)returna+"+"+b+"i";returna+"";}publicdoublegetRealPart(){returna;}publicdoublegetImaginaryPart(){returnb;}@Override/**ImplementtheclonemethodintheObjectclass*/publicObjectclone(){//Implementittry{returnsuper.clone();//Automaticallyperformashallowcopy}catch(CloneNotSupportedExceptionex){returnnull;}}}18publicclassExercise13_18{publicstaticvoidmain(String[]args){finalintN=100;Rationalsum=newRational();for(inti=1;i<=N;i++)sum=sum.add(newRational(i-1,i));

System.out.println("Thesumofthefirstseriesis"+sum+"="+sum.doubleValue());}}19importjava.math.BigInteger;importjava.util.Scanner;publicclassExercise13_19{publicstaticvoidmain(String口args){Scannerinput=newScanner(System.in);System.out.print("Enteradecimal:");Stringdecimal=input.nextLine();System.out.println("Thefractionnumberis"+getFraction(decimal));}privatestaticRationalgetFraction(Stringdecimal){String[]items=decimal.split("[.]");if(items.length==1){returnnewRational(newBigInteger(items[0]),BigInteger.ONE);}else{Rationalr=newRational(newBigInteger(items[0]+items[1]),getDenominator(items[1].length()));returnr;}}privatestaticBigIntegergetDenominator(intsize){BigIntegerresult=BigInteger.ONE;for(inti=0;i<size;i++)result=result.multiply(newBigInteger("10"));returnresult;}staticclassRationalextendsNumberimplementsComparable<Rational>{//DatafieldsfornumeratoranddenominatorprivateBigIntegernumerator=BigInteger.ZERO;privateBigIntegerdenominator=BigInteger.ONE;

/**Constructarationalwithdefaultproperties*/publicRational。{this(BigInteger.ZERO,BigInteger.ONE);}/**Constructarationalwithspecifiednumeratoranddenominator*/publicRational(BigIntegernumerator,BigIntegerdenominator){BigIntegergcd=gcd(numerator,denominator);if(pareTo(BigInteger.ZERO)<0)this.numerator=numerator.multiply(newBigInteger("-1")).divide(gcd);elsethis.numerator=numerator.divide(gcd);this.denominator=denominator.abs().divide(gcd);}/**FindGCDoftwonumbers*/privatestaticBigIntegergcd(BigIntegern,BigIntegerd){BigIntegern1=n.abs();BigIntegern2=d.abs();BigIntegergcd=BigInteger.ONE;for(BigIntegerk=BigInteger.ONE;pareTo(n1)<=0&&pareTo(n2)<=0;k=k.add(BigInteger.ONE)){if(n1.remainder(k).equals(BigInteger.ZERO)&&n2.remainder(k).equals(BigInteger.ZERO))gcd=k;}returngcd;}/**Returnnumerator*/publicBigIntegergetNumerator(){returnnumerator;}/**Returndenominator*/publicBigIntegergetDenominator(){returndenominator;}

/**Addarationalnumbertothisrational*/publicRationaladd(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getDenominator()).add(denominator.multiply(secondRational.getNumerator()));BigIntegerd=denominator.multiply(secondRational.getDenominator());returnnewRational(n,d);}/**Subtractarationalnumberfromthisrational*/publicRationalsubtract(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getDenominator()).subtract(denominator.multiply(secondRational.getNumerator()));BigIntegerd=denominator.multiply(secondRational.getDenominator());returnnewRational(n,d);}/**Multiplyarationalnumbertothisrational*/publicRationalmultiply(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getNumerator());BigIntegerd=denominator.multiply(secondRational.getDenominator());returnnewRational(n,d);}/**Dividearationalnumberfromthisrational*/publicRationaldivide(RationalsecondRational){BigIntegern=numerator.multiply(secondRational.getDenominator());BigIntegerd=denominator.multiply(secondRational.numerator);returnnewRational(n,d);}@OverridepublicStringtoString(){if(denominator.equals(BigInteger.ONE))returnnumerator+"";elsereturnnumerator+"/"+denominator;}@Override/**OverridetheequalsmethodintheObjectclass*/publicbooleanequals(Objectparml){if((this.subtract((Rational)(parm1))).getNumerator().equals(BigInteger.ONE))returntrue;elsereturnfalse;

@Override/**OverridethehashCodemethodintheObjectclass*/publicinthashCode(){returnnewDouble(this.doubleValue()).hashCode();}@Override/**OverridetheabstractintValuemethodinjava.lang.Number*/publicintintValue(){return(int)doubleValue();}@Override/**OverridetheabstractfloatValuemethodinjava.lang.Number*/publicfloatfloatValue(){return(float)doubleValue();}@Override/**OverridethedoubleValuemethodinjava.lang.Number*/publicdoubledoubleValue(){returnnumerator.doubleValue()/denominator.doubleValue();}@Override/**OverridetheabstractlongValuemethodinjava.lang.Number*/publiclonglongValue(){return(long)doubleValue();}@OverridepublicintcompareTo(Rationalo){if((this.subtract((Rational)o)).getNumerator().compareTo(BigI