《Java語言程序設(shè)計(基礎(chǔ)篇)》(第10版 梁勇 著)第三章練習題答案

《Java（基礎(chǔ)篇（10）第三章練習題答案3.1publicclassExercise03_01{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);System.out.print("Entera,b,c:");doublea=input.nextDouble();doubleb=input.nextDouble();doublec=input.nextDouble();doublediscriminant=b*b-4*a*c;if(discriminant<0){System.out.println("Theequationhasnorealroots");}elseif(discriminant==0){doubler1=-b/(2*a);System.out.println("Theequationhasoneroot"+r1);}else{//(discriminant>0)doubler1=(-b+Math.pow(discriminant,0.5))/(2*a);doubler2=(-b-Math.pow(discriminant,0.5))/(2*a);System.out.println("Theequationhastworoots"+r1+"and"+r2);}}}附加publicclassExercise03_01Extra{publicstaticvoidmain(Stringargs[]){Scannerinput=newScanner(System.in);System.out.print("Enteranumerator:");intnumerator=input.nextInt();System.out.print("Enteradenominator:");intdenominator=input.nextInt();if(numerator<denominator){System.out.println(numerator+"/"+denominator+"isaproperfraction");}");

elseif(numerator%denominator==0){System.out.print(numerator+"/"+denominator+"isanimproperfractionSystem.out.println("anditcanbereducedto"+numerator/denominator);");

}else{System.out.print(numerator+"/"+denominator+"isanimproperfractionSystem.out.println("anditsmixedfractionis"+numerator/denominator+"+"+}}}

numerator%denominator+"/"+denominator);3.2publicclassExercise03_02{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);intnumber1=(int)(System.currentTimeMillis()%10);intnumber2=(int)(System.currentTimeMillis()*7%10);intnumber3=(int)(System.currentTimeMillis()*3%10);System.out.print("Whatis"+number1+"+"+number2+"+"+number3+"?");intanswer=input.nextInt();System.out.println(number1+"+"+number2+"+"+number3+"="+answer+"is"+(number1+number2+number3==answer));}}附加publicclassExercise03_02Extra{publicstaticvoidmain(Stringargs[]){Scannerinput=newScanner(System.in);System.out.print("Enterthecoordinatesfortwopoints:");doublex1=input.nextDouble();doubley1=input.nextDouble();doublex2=input.nextDouble();doubley2=input.nextDouble();doublem=(y2-y1)/(x2-x1);doubleb=y1-m*x1;System.out.print("Thelineequationfortwopoints("+x1+","+y1+")and("+x2+","+y2+")is"+"y=");if(m==-1)System.out.print("-x");elseif(m==1)System.out.print("x");elseSystem.out.print(m+"x");if(b>0)System.out.println("+"+b);elseif(b<0)System.out.println("-"+(-1*b));else//bis0System.out.println();}}3.3publicclassExercise03_03{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);System.out.print("Entera,b,c,d,e,f:");doublea=input.nextDouble();doubleb=input.nextDouble();doublec=input.nextDouble();doubled=input.nextDouble();doublee=input.nextDouble();doublef=input.nextDouble();doubledetA=a*d-b*c;if(detA==0){System.out.println("Theequationhasnosolution");}else{doublex=(e*d-b*f)/detA;doubley=(a*f-e*c)/detA;System.out.println("xis"+x+"andyis"+y);}}}3.3附加publicclassExercise03_03Extra{publicstaticvoidmain(String[]args){finaldoubleRADIUS=5;doubleangle=Math.random()*2*Math.PI;doublex=RADIUS*Math.random()*Math.cos(angle);doubley=RADIUS*Math.sin(angle);doubledistance=Math.pow(x*x+y*y,0.5);System.out.println("Thepointis("+x+","+y+")anditsdistancetothecenteris"+distance);}}3.4publicclassExercise03_04{publicstaticvoidmain(String[]args){intnumber=(int)(Math.random()*12)+1;//orintnumber=(int)(System.currentTimeMillis()%12+1);//orintnumber=(int)(Math.random()*12)+1;if(number==1)System.out.println("MonthisJanuaray");elseif(number==2)System.out.println("MonthisFeburary");elseif(number==3)System.out.println("MonthisMarch");elseif(number==4)System.out.println("MonthisApril");elseif(number==5)System.out.println("MonthisMay");elseif(number==6)System.out.println("MonthisJune");elseif(number==7)System.out.println("MonthisJuly");elseif(number==8)System.out.println("MonthisAugust");elseif(number==9)System.out.println("MonthisSeptember");elseif(number==10)System.out.println("MonthisOctober");elseif(number==11)System.out.println("MonthisNovember");else//if(number==12)System.out.println("MonthisDecember");}}3.5publicclassExercise03_05{publicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//PrompttheusertoenteranintegerfortodaySystem.out.print("Entertoday抯day);inttoday=input.nextInt();System.out.print("Enterthenumberofdayselapsedsincetoday:");intelapsedDays=input.nextInt();StringnameForToday;if(today==0)nameForToday="Sunday";elseif(today==1)nameForToday="Monday";elseif(today==2)nameForToday="Tuesday";elseif(today==3)nameForToday="Wednesday";elseif(today==4)nameForToday="Thursday";elseif(today==5)nameForToday="Friday";else//if(today==6)nameForToday="Saturday";intfutureDay=(today+elapsedDays)%7;StringnameForFutureDay;if(futureDay==0)nameForFutureDay="Sunday";elseif(futureDay==1)nameForFutureDay="Monday";elseif(futureDay==2)nameForFutureDay="Tuesday";elseif(futureDay==3)nameForFutureDay="Wednesday";elseif(futureDay==4)nameForFutureDay="Thursday";elseif(futureDay==5)nameForFutureDay="Friday";else//if(futureDay==6)nameForFutureDay="Saturday";System.out.println("Todayis"+nameForToday+"andthefuturedayis"+nameForFutureDay);}}3.6publicclassExercise03_06{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);//PrompttheusertoenterweightinpoundsSystem.out.print("Enterweightinpounds:");doubleweight=input.nextDouble();//PrompttheusertoenterheightSystem.out.print("Enterfeet:");doublefeet=input.nextDouble();System.out.print("Enterinches:");doubleinches=input.nextDouble();doubleheight=feet*12+inches;//ComputeBMIdoublebmi=weight*0.45359237/((height*0.0254)*(height*0.0254));//DisplayresultSystem.out.println("BMIis"+bmi);if(bmi<18.5)System.out.println("Underweight");elseif(bmi<25)System.out.println("Normal");elseif(bmi<30)System.out.println("Overweight");elseSystem.out.println("Obese");}}3.7/**BreakdownanamountintosmallerunitsDisplaythenon-zerodenominationsonly,anddisplaysingularwordsforsingleunitslike1dollars,1penny,anddisplaypluralwordsformorethanoneunitlike2dollars,3pennies.*/publicclassExercise03_07{//Mainmethodpublicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//ReceivetheamountenteredfromthekeyboardSystem.out.print("Enteranamountindouble,forexample11.56:");doubleamount=input.nextDouble();intremainingAmount=(int)(amount*100);//FindthenumberofonedollarsintnumberOfOneDollars=remainingAmount/100;remainingAmount=remainingAmount%100;//FindthenumberofquartersintheremainingamountintnumberOfQuarters=remainingAmount/25;remainingAmount=remainingAmount%25;//FindthenumberofdimesintheremainingamountintnumberOfDimes=remainingAmount/10;remainingAmount=remainingAmount%10;//FindthenumberofnickelsintheremainingamountintnumberOfNickels=remainingAmount/5;remainingAmount=remainingAmount%5;//FindthenumberofpenniesintheremainingamountintnumberOfPennies=remainingAmount;//Displayresultsif(amount<0){System.out.println("Youramountisnegative");System.exit(1);}elseif(amount<0){System.out.println("Youramountiszero");System.exit(2);}System.out.println("Youramount"+amount+"consistsof");if(numberOfOneDollars>1)System.out.println(numberOfOneDollars+"\tdollars");elseif(numberOfOneDollars==1)System.out.println(numberOfOneDollars+"\tdollar");if(numberOfQuarters>1)System.out.println(numberOfQuarters+"\tquarters");elseif(numberOfQuarters==1)System.out.println(numberOfQuarters+"\tquarter");if(numberOfDimes>1)System.out.println(numberOfDimes+"\tdimes");elseif(numberOfDimes==1)System.out.println(numberOfDimes+"\tdime");if(numberOfNickels>1)System.out.println(numberOfNickels+"\tnickels");elseif(numberOfNickels==1)System.out.println(numberOfNickels+"\tnickel");if(numberOfPennies>1)System.out.println(numberOfPennies+"\tpennies");elseif(numberOfPennies==1)System.out.println(numberOfPennies+"\tpenny");}}3.8publicclassExercise03_08{publicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//EnterthreenumbersSystem.out.print("Enterthreeintegers:");intnumber1=input.nextInt();intnumber2=input.nextInt();intnumber3=input.nextInt();if(number1>number2){inttemp=number1;number1=number2;number2=temp;}if(number2>number3){inttemp=number2;number2=number3;number3=temp;}if(number1>number2){inttemp=number1;number1=number2;number2=temp;}System.out.println("Thesortednumbersare"+number1+""+number2+""+number3);}}3.9publicclassExercise03_09{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);//PrompttheusertoenteranintegerSystem.out.print("Enterthefirst9digitsofanISBNasinteger:");intnumber=input.nextInt();//Calculatechecksum(YoumaywritealooptosimplifyitinCh4intchecksum=((number/100000000%10)*1+(number/10000000%10)*2+(number/1000000%10)*3+(number/100000%10)*4+(number/10000%10)*5+(number/1000%10)*6+(number/100%10)*7+(number/10%10)*8+(number%10)*9)%11;System.out.print("TheISBN-10numberis");//Displayleadingzeros,improvethesolutionusingloopsinthenextchapterif(number/100000000==0){System.out.print("0");if(number/10000000==0){System.out.print("0");if(number/1000000==0){System.out.print("0");if(number/100000==0){System.out.print("0");if(number/10000==0){System.out.print("0");if(number/1000==0){System.out.print("0");if(number/100==0){System.out.print("0");if(number/10==0){System.out.print("0");if(number==0){System.out.print("0");}}}}}}}}}System.out.print(number);if(checksum==10)System.out.print("X");elseSystem.out.print(checksum);}}3.10publicclassExercise03_10{publicstaticvoidmain(String[]args){//1.Generatetworandomsingle-digitintegersintnumber1=(int)(Math.random()*10);intnumber2=(int)(Math.random()*10);//2.Promptthestudenttoanswer搘hatisnumber1+number2??System.out.print("Whatis"+number1+"+"+number2+"?");Scannerinput=newScanner(System.in);intanswer=input.nextInt();//4.GradetheansweranddisplaytheresultStringreplyString;if(number1+number2==answer)replyString="Youarecorrect!";elsereplyString="Youransweriswrong.\n"+number1+"+"+number2+"shouldbe"+(number1+number2);System.out.println(replyString);}}3.11publicclassExercise03_11{publicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//PrompttheusertoenterinputSystem.out.print("Enteramonthintheyear(e.g.,1forJan):");intmonth=input.nextInt();System.out.print("Enterayear:");intyear=input.nextInt();intnumberOfDaysInMonth=0;switch(month){case1:System.out.print("January"+year);numberOfDaysInMonth=31;break;case2:System.out.print("February"+year);if(year%400==0||(year%4==0&&year%100!=0)){numberOfDaysInMonth=29;}else{numberOfDaysInMonth=28;}break;case3:System.out.print("March"+year);numberOfDaysInMonth=31;break;case4:System.out.print("April"+year);numberOfDaysInMonth=30;break;case5:System.out.print("May"+year);numberOfDaysInMonth=31;break;case6:System.out.print("June"+year);numberOfDaysInMonth=30;break;case7:System.out.print("July"+year);numberOfDaysInMonth=31;break;case8:System.out.print("August"+year);numberOfDaysInMonth=31;break;case9:System.out.print("September"+year);numberOfDaysInMonth=30;break;case10:System.out.print("October"+year);numberOfDaysInMonth=31;break;case11:System.out.print("November"+year);numberOfDaysInMonth=30;break;case12:System.out.print("December"+year);numberOfDaysInMonth=31;break;}System.out.print("has"+numberOfDaysInMonth+"days");}}3.12publicclassExercise03_12{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);System.out.print("Enterathree-digitinteger:");intnumber=input.nextInt();if(number/100==number%10)System.out.println(number+"isapalindrome");elseSystem.out.println(number+"isnotapalindrome");}}3.13publicclassExercise03_13{publicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//PrompttheusertoenterfilingstatusSystem.out.print("(0-singlefiler,1-marriedjointlyorqualifyingwidow(er),"+"\n2-marriedseparately,3-headofhousehold)\n"+"Enterthefilingstatus:");intstatus=input.nextInt();//PrompttheusertoentertaxableincomeSystem.out.print("Enterthetaxableincome:");doubleincome=input.nextDouble();//Computetaxdoubletax=0;if(status==0){//Computetaxforsinglefilersif(income<=8350){tax=income*0.10;}elseif(income<=33950){tax=8350*0.10+(income-8350)*0.15;}elseif(income<=82250){tax=8350*0.10+(33950-8350)*0.15+(income-*0.25;}elseif(income<=171550){tax=8350*0.10+(33950-8350)*0.15+(82250-33950)*0.25+(income-82250)*0.28;}elseif(income<=372950){tax=8350*0.10+(33950-8350)*0.15+(82250-33950)*0.25+(171550-82250)*0.28+(income-171550)*0.33;}else{tax=8350*0.10+(33950-8350)*0.15+(82250-33950)*0.25+(171550-82250)*0.28+(372950-171550)*0.33+(income-372950)*0.35;}}elseif(status==1){//Computetaxformarriedfilejointlyif(income<=16700){tax=income*0.10;}elseif(income<=67900){tax=16700*0.10+(income-16700)*0.15;}elseif(income<=137050){tax=16700*0.10+(67900-16700)*0.15+(income-67900)*0.25;}elseif(income<=208850){tax=16700*0.10+(67900-16700)*0.15+(137050-67900)*0.25+(income-137050)*0.28;}elseif(income<=372950){tax=16700*0.10+(67900-16700)*0.15+(137050-67900)*0.25+(208850-137050)*0.28+(income-208850)*0.33;}else{tax=16700*0.10+(67900-16700)*0.15+(137050-67900)*0.25+(171950-137050)*0.28+(372950-208850)*0.33+(income-372950)*0.35;}}elseif(status==2){//Computetaxformarriedseparatelyif(income<=8350){tax=income*0.10;}elseif(income<=33950){tax=8350*0.10+(income-8350)*0.15;}elseif(income<=68525){tax=8350*0.10+(33950-8350)*0.15+(income-33950)*0.25;}elseif(income<=104425){tax=8350*0.10+(33950-8350)*0.15+(68525-33950)*0.25+(income-68525)*0.28;}elseif(income<=186475){tax=8350*0.10+(33950-8350)*0.15+(68525-33950)*0.25+(104425-68525)*0.28+(income-104425)*0.33;}else{tax=8350*0.10+(33950-8350)*0.15+(68525-33950)*0.25+(104425-68525)*0.28+(186475-104425)*0.33+(income-186475)*0.35;}}elseif(status==3){//Computetaxforheadofhouseholdif(income<=11950){tax=income*0.10;}elseif(income<=45500){tax=11950*0.10+(income-11950)*0.15;}elseif(income<=117450){tax=11950*0.10+(45500-11950)*0.15+(income-45500)*0.25;}elseif(income<=190200){tax=11950*0.10+(45500-11950)*0.15+(117450-45500)*0.25+(income-117450)*0.28;}elseif(income<=372950){tax=11950tax=11950*+(190200else{0.10+(45500-11950)*0.15+(117450-45500)-117450)*0.28+(income-190200)*0.33;*0.25tax=11950*0.10+(45500-11950)*0.15+(117450-45500)*0.25+(190200-117450)*0.28+(372950-190200)*0.33+(income-372950)*0.35;}}else{System.out.println("Error:Wrongfilingstatus");System.exit(1);}//DisplaytheresultSystem.out.println("Taxis"+(int)(tax*100)/100.0);}}3.14publicclassExercise03_14{publicstaticvoidmain(String[]args){//Obtaintherandomnumber0or1intnumber=(int)(Math.random()*2);//Prompttheusertoenteraguessjava.util.Scannerinput=newjava.util.Scanner(System.in);System.out.print("Guessheadortail?"+"Enter0forheadand1fortail:");intguess=input.nextInt();//Checktheguessif(guess==number)System.out.println("Correctguess");elseif(number==0)System.out.println("Sorry,itisahead");elseSystem.out.println("Sorry,itisatail");}}3.15publicclassExercise03_15{publicstaticvoidmain(String[]args){//Generatealotteryintlottery=(int)(Math.random()*1000);//Prompttheusertoenteraguessjava.util.Scannerinput=newjava.util.Scanner(System.in);System.out.print("Enteryourlotterypick(threedigits):");intguess=input.nextInt();//Getdigitsintl1=lottery/100;intl2=(lottery%100)/10;//l2=(lottery/10)%10intl3=lottery%10;intg1=guess/100;intg2=(guess%100)/10;intg3=guess%10;System.out.println("Lotteryis"+lottery);//Checktheguessif(guess==lottery)System.out.println("Exactmatch:youwin$10,000");elseif(g1==l1&&g3==l2&&g2==l3||g2==l1&&g1==l2&&g3==l3||g2==l1&&g3==l2&&g1==l3||g3==l1&&g1==l2&&g2==l3||g3==l1&&g2==l2&&g1==l3)System.out.println("Matchalldigits:youwin$3,000");elseif(g1==l1||g1==l2||g1==l3||g2==l1||g2==l2||g2==l3||g3==l1||g3==l2||g3==l3)System.out.println("Matchonedigit:youwin$1,000");elseSystem.out.println("Sorry,nomatch");}}3.16publicclassExercise03_16{publicstaticvoidmain(String[]args){doublex=Math.random()*100-50;doubley=Math.random()*200-100;System.out.println(x+","+y);}}3.17publicclassExercise03_17{publicstaticvoidmain(String[]args){//Generatescissor,rock,paperintcomputerNumber=(int)(Math.random()*3);//Prompttheusertoenterscissor,rock,orpaperjava.util.Scannerinput=newjava.util.Scanner(System.in);System.out.print("scissor(0),rock(1),paper(2):");intuserNumber=input.nextInt();//Checktheguessswitch(computerNumber){case0:if(userNumber==0)System.out.print("Thecomputerisscissor.Youarescissortoo.Itisadraw");elseif(userNumber==1)(ers.ue.uelseif(userNumber==2)System.out.print("Thecomputerisscissor.Youarepaper.Youlost");break;case1:if(userNumber==0)System.out.print("Thecomputerisrock.Youarescissor.Youlost");elseif(userNumber==1)System.out.print("Thecomputerisrock.Youarerocktoo.Itisadraw");

elseif(userNumber==2)System.out.print("Thecomputerisrock.Youarepaper.Youwon");break;case2:if(userNumber==0)System.out.print("Thecomputerispaper.Youarescissor.Youwon");elseif(userNumber==1)System.out.print("Thecomputerispaper.Youarerock.Youelseif(userNumber==2)System.out.print("Thecomputerispaper.Youarepapertoo.Itisadraw");break;}}}3.18publicclassExercise03_18{publicstaticvoidmain(Stringargs[]){Scannerinput=newScanner(System.in);System.out.print("Enterpackageweight:");doublew=input.nextDouble();if(w<=1){System.out.println("Theshippingcostis$3.5");}elseif(w<=3){System.out.println("Theshippingcostis$5.5");}elseif(w<=10){System.out.println("Theshippingcostis$8.5");}elseif(w<=20){System.out.println("Theshippingcostis$10.5");}else{System.out.println("Thepackagecannotbeshipped");}}}3.19publicclassExercise03_19{publicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//EnterthreeedgesSystem.out.print("Enterthreeedges(lengthindouble):");doubleedge1=input.nextDouble();doubleedge2=input.nextDouble();doubleedge3=input.nextDouble();//DisplayresultsbooleanisValid=(edge1+edge2>edge3)&&(edge1+edge3>edge2)&&(edge2+edge3>edge1);//Displayresultsif(isValid){System.out.println("Theperimeteris"+(edge1+edge2+edge3));}else{System.out.println("Inputisinvalid");}}}3.20publicclassExercise03_20{//Mainmethodpublicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//EnterthetemperatureinFahrenheitSystem.out.print("EnterthetemperatureinFahrenheit:");doublefahrenheit=input.nextDouble();if(fahrenheit<-58||fahrenheit>41){System.out.println("Temperaturemustbebetween-58and41");System.exit(1);}//EnterthewindspeedmilesperhourSystem.out.print("Enterthewindspeedmilesperhour:");doublespeed=input.nextDouble();if(speed<2){System.out.println("Speedmustbegreaterthanorequalto2");System.exit(2);}//ComputewindchillindexdoublewindChillIndex=35.74+0.6215*fahrenheit-35.75*Math.pow(speed,0.16)+0.4275*fahrenheit*Math.pow(speed,0.16);//DisplaytheresultSystem.out.println("Thewindchillindexis"+windChillIndex);}}3.21publicclassExercise03_21{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);System.out.print("Enteryear:(e.g.,2008):");intyear=input.nextInt();System.out.print("Entermonth:1-12:");intmonth=input.nextInt();if(month==1){month=13;year=year-1;//Januaryiscountedasmonth13ofthepreviousyear.}elseif(month==2){month=14;year=year-1;//Februaryiscountedasmonth14ofthepreviousyear.}System.out.print("Enterthedayofthemonth:1-31:");intdayOfMonth=input.nextInt();intj=year/100;intk=year%100;intdayOfWeek=(dayOfMonth+26*(month+1)/10+k+k/4+j/4+5*j)%7;if(dayOfWeek==0)System.out.println("DayoftheweekisSaturday");elseif(dayOfWeek==1)System.out.println("DayoftheweekisSunday");elseif(dayOfWeek==2)System.out.println("DayoftheweekisMonday");elseif(dayOfWeek==3)System.out.println("DayoftheweekisTuesday");elseif(dayOfWeek==4)System.out.println("DayoftheweekisWednesday");elseif(dayOfWeek==5)System.out.println("DayoftheweekisThursday");elseif(dayOfWeek==6)System.out.println("DayoftheweekisFriday");}}3.22publicclassExercise03_22{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);//EnterapointwithtwodoublevaluesSystem.out.print("Enterapointwithtwocoordinates:");doublex=input.nextDouble();doubley=input.nextDouble();//Computethedistancedoubledistance=Math.pow(x*x+y*y,0.5);if(distance<=10)System.out.println("Point("+x+","+y+")isinthecircle");elseSystem.out.println("Point("+x+","+y+")isnotinthecircle");}}3.23publicclassExercise03_23{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);//EnterapointwithtwodoublevaluesSystem.out.print("Enterapointwithtwocoordinates:");doublex=input.nextDouble();doubley=input.nextDouble();//ComputethehorizontaldistancetothecenteroftherectangledoublehDistance=Math.pow(x*x,0.5);//ComputetheverticaldistancetothecenteroftherectangledoublevDistance=Math.pow(y*y,0.5);if(hDistance<=5&&vDistance<=2.5)System.out.println("Point("+x+","+y+")isintherectangle");elseSystem.out.println("Point("+x+","+y+")isnotintherectangle");}}3.24publicclassExercise03_24{publicstaticvoidmain(String[]args){finalintNUMBER_OF_CARDS=52;//Pickacardintnumber=(int)(Math.random()*NUMBER_OF_CARDS);System.out.print("Thecardyoupickedis");if(number%13==0)System.out.print("Aceof");elseif(number%13==10)System.out.print("Jackof");elseif(number%13==11)System.out.print("Queenof");elseif(number%13==12)System.out.print("Kingof");elseSystem.out.print((number%13)+"of");if(number/13==0)System.out.println("Clubs");elseif(number/13==1)System.out.println("Diamonds");elseif(number/13==2)System.out.println("Hearts");elseif(number/13==3)System.out.println("Spades");}}3.25publicclassExercise03_25{publicstaticvoidmain(String[]args){Scannerinput=newScanner(System.in);System.out.print("Enterx1,y1,x2,y2,x3,y3,x4,y4:");doublex1=input.nextDouble();doubley1=input.nextDouble();doublex2=input.nextDouble();doubley2=input.nextDouble();doublex3=input.nextDouble();doubley3=input.nextDouble();doublex4=input.nextDouble();doubley4=input.nextDouble();abcde=====(y1-y2);-(x1-x2);(y3-y4);-(x3-x4);(y1-y2)*x1-(x1-x2)*y1;doublef=(y3-y4)*x3-(x3-x4)*y3;doubledetA=a*d-b*c;if(detA==0){System.out.println("Thetwolinesareparallel");}else{doublex=(e*d-b*f)/detA;doubley=(a*f-e*c)/detA;System.out.println("Theintersectingpointisat("+x+","+y+")");}}}3.26publicclassExercise03_26{publicstaticvoidmain(String[]args){java.util.Scannerinput=newjava.util.Scanner(System.in);//EnteranintegerSystem.out.print("Enteraninteger:");intnumber=input.nextInt();System.out.println("Is"+number+"divisibleby5and6?"+((number%5==0)&&(number%6==0)));System.out.println("Is"+number+"divisibleby5or6?"+((number%5==0)||(number%6==0)));System.out.println("Is"+number+"divisibleby5or6,butnotboth?"+((number%5==0)^(number%6==0)));}}3.27publicclassExercise03_27{publicstaticvoidmain(Stringargs[]){Scannerinput=newScanner(System.in);System.out.print("Enterapoint'sx-andy-coordinates:");doublex=input.nextDouble();doubley=input.nextDouble();if(x>200||x<0||y>100||y<0)System.out.println("Thepointisnotinthetriangle");else{doubleslope=(100.0-0)/(0-200);doubleslope1=y/(x-200.0);if(slope1>slope)System.out.println("Thepointisinthetriangle");elseSystem.out.println("Thepointisnotinthetriangle");}}}3.28publicclassExercise03_28{publicstaticvoidmain(Stringargs[]){Scannerinput=newScanner(System.in);");");

System.out.print("Enterr1抯centerx-y-coordinateswidthandheight:doublex1=input.nextDouble();doubley1=input.nextDouble();doublew1=input.nextDouble();doubleh1=input.nextDouble();System.out.print("Enterr2抯centerx-y-coordinateswidthandheight:doublex2=input.nextDouble();doubley2=input.nextDouble();doublew2=input.nextDouble();doubleh2=input.nextDouble();doublexDistance=x1>=x2?x1-x2:x2-x1;doubleyDistance=y1>=y2?y1-y2:y2-y1;if(xDistance<=(w1-w2)/2&&yDistance<=(h1-h2)/2)System.out.println("r2isinsider1");elseif(xDistance<=(w1+w2)/2&&yDistance<=(h1+h2)/2)System.out