Cs 38 Ch 5

Front 1

20554: Given the char variable c, write an expression that is true if and only if the value of c is not the space character.

Back 1

c != ' '

Front 2

20552: Write an expression that evaluates to true if and only if the value of the integer variable x is equal to zero.

Back 2

x == 0

Front 3

20553: Write an expression that evaluates to true if and only if the variables profits and losses are exactly equal.

Back 3

profits == losses

Front 4

20667: Write an expression that evaluates to true if the integer variable x contains an even value, and false if it contains an odd value.

Back 4

x%2 == 0

Front 5

20665: Write an expression that evaluates to true if the value of the integer variable numberOfPrizes is divisible (with no remainder) by the integer variable numberOfParticipans. Assume that numberOfParticipants is not zero.

Back 5

numberOfPrizes%numberOfParticipants == 0

Front 6

20890: Assume that c is a char variable has been declared and already given a value. Write an expression whose value is true if and only if c is a newline character.

Back 6

c == '\n'

Front 7

20608: Write an expression that evaluates to true if and only if the integer x is greater than the integer y.

Back 7

x > y

Front 8

20556: Working overtime is defined as having worked more than 40 hours during the week. Given the variable hoursWorked, write an expression that evaluates to true if the employee worked overtime.

Back 8

hoursWorked > 40

Front 9

20559: Given a double variable called average, write an expression that is true if and only if the variable’s value is less than 60.0.

Back 9

average<60.0

Front 10

20560: Given an int variable grossPay, write an expression that evaluates to true if an donly if the value of grossPay is less than 10,000.

Back 10

grossPay<10000

(DON'T PUT COMMA)

Front 11

20920: Assume that x is a char variable has been declared and already given a value. Write an expression whose value is true if and only if x is NOT a letter.

Back 11

!(x>='a' && x<='z') && !(x>='A' && x<='Z')

Front 12

20561: Given that the variables x and y have already been declared and assigned values, write an expression that evaluates to true is x is non-negative and y is negative.

Back 12

x >= 0 && y < 0

Front 13

20563: Given two variables, isEmpty of type boolean, indicating whether a class roster is empty or not, and numberOfCredits of type int, containing the number of credits for a class, write an expression that evaluates to true if the class roster is empty or the class is exactly three credits.

Back 13

(isEmpty == true) || (numberOfCredits == 3)

Front 14

20564: Given two variables, isEmpty of type boolean, indicating whether a class roster is empty or not, and numberOfCredits of type int, containing the number of credits for a class, write an expression that evaluates to true if the class roster is not empty and the class is more than two credits.

Back 14

(isEmpty != true) && (numberOfCredits > 2)

Front 15

20565: Given two variables, isEmpty of type boolean, indicating whether a class roster is empty or not, and numberOfCredits of type int, containing the number of credits for a class, write an expression that evaluates to true if the class roster is not empty and the class is one or three credits.

Back 15

(isEmpty != true) && (numberOfCredits==1 || numberOfCredits==3)

Front 16

20893: Assume that c is a char variable has been declared and already given a value. Write an expression whose value is true if and only if c is what is called a whitespace character (that is a space or a tab or a newline—none of which result in ink being printed on paper).

Back 16

(c == ' ') || (c == '\t') || (c == '\n')

Front 17

20894: Assume that c is a char variable has been declared and already given a value. Write an expression whose value is true if and only if c is NOT what is called a whitespace character (that is a space or a tab or a newline—none of which result in ink being printed on paper).

Back 17

(c != ' ') && (c != '\t') && (c != '\n')

Front 18

20613: Write an expression that evaluates to true if and only if value of the boolean variable isAMember is false.

Back 18

isAMember != true

Front 19

20673: Write a statement that toggles the value of onOffSwitch. That is, if onOffSwitch is false, its value is changed to true; if onOffSwitch is true, its value is changed to false.

Back 19

if (onOffSwitch==false)
onOffSwitch=true;
else
onOffSwitch=false;

Front 20

20921: Assume that a boolean variable isQuadrilateral has been declared, and that another variable, numberOfSides has been declared and initialized. Write a statement that assigns the value true if numberOfSides is exactly 4 and false otherwise.

Back 20

if (numberOfSides == 4)

isQuadrilateral = true;

else

isQuadrilateral = false;

(boolean... "=" は一つだけ)

Front 21

20946: Clucker Motors Inc. is recalling all vehicles from model years 2001-2006. A boolean variable named norecall has been declared. Given a variable modelYear write a statement that assigns true to norecall if the value of modelYear does NOT within the recall range and assigns false otherwise. Do not use an if statement in this exercise!

Back 21

norecall = !(modelYear >=2001 && modelYear <=2006);

Front 22

20941: Clunker Motors Inc is recalling all vehicles from model years 1995-1998 and 2004-2006. A boolean variable named recalled has been declared. Given a variable modelYear write a statement that assigns true to recalled if the value of modelYear falls within the two recall ranges and assigns false otherwise. Do not use an if statement in this exercise!

Back 22

recalled = (modelYear >=1995 && modelYear <= 1998) || (modelYear >= 2004 && modelYear <= 2006);

Front 23

20942: Clunker Motos Inc. is recalling all vehicles from model years 1995-1998 and 2004-2006. A boolean variable named recalled has been declared. Given a variable modelYear write a statement that assigns true to norecall if the valueof modelYear does NOT fall within the two recall ranges and assigns false otherwise. Do not use an if statement in this exercise!

Back 23

norecall = !(modelYear >=1995 && modelYear <= 1998) && !(modelYear >= 2004 && modelYear <= 2006);

Front 24

20756: Assign to the boolean variable ‘possibleCandidate’ the value false if the int variable ‘n’ is even and greater than 2, or if the variable ‘n’ is less than or equal to 0; otherwise, assign true to ‘possibleCandidate’. Assume ‘possibleCandidate’ and ‘n’ are already declared and ‘n’ assigned a value.

Back 24

if (((n%2 == 0) && (n>2)) || (n <= 0))
possibleCandidate = false;
else
possibleCandidate = true;

Front 25

20616: Write a conditional that decreases the variable shelfLife by 4 if the variable outside Temperature is greater than 90.

Back 25

if (outsideTemperature > 90)
shelfLife = shelfLife -4;

Front 26

20617: Write a conditional that multiplies the value of the variable pay by one-and-a-half if the value of the boolean variable workedOvertime is true.

Back 26

if (workedOvertime == true)
pay = pay * 1.5;

(true/false は、イコール２つ)

Front 27

20932: Clunker Motors Inc. is recalling all vehicles from model years 1995-1998 and 2004-2006. Given a variable modelYear write a statement that prints the message “RECALL” to standard output if the value of modelYear falls within those two ranges.

Back 27

if ((modelYear>=1995 && modelYear<=1998) || (modelYear>=2004 && modelYear<=2006))
System.out.println("RECALL");

Front 28

20927: Assume that the variables gpa, deansList and studentName, have been declared and initialized. Write a statement that adds 1 to deansList and prints studentName to standard out if gpa exceeds 3.5.

Back 28

if (gpa > 3.5)
{
deansList = deansList + 1;
System.out.println(studentName);
}

Front 29

20934: Clunker Motors Inc is recalling all vehicles in its Extravagent line from model years 1999-2002. A boolean variable named recalled has been declared. Given a variable modelYear and a String modelName write a statement that assigns true to recalled is the values of modelYear and modelName match the recall details and assigns false otherwise.

Back 29

if ((modelYear>=1999 && modelYear<=2002) && (modelName == "Extravagant"))
recalled = true;
else
recalled = false;

(modelName... イコール二つ、""をつける)

Front 30

20945: Clunker Motors Inc. is recalling all vehicles from model years 2001-2006. Given a variable modelYear write a statement that prints the message “NO RECALL” to standard output if the value of modelYear DOES NOT fall within that range.

Back 30

if (!(modelYear>=2001 && modelYear<=2006))
System.out.println("NO RECALL");

Front 31

20619: Write an if/else statement that compares the value of the variables soldYesterday and soldToday, and based upon that comparison assigns salesTrend the value -1 or 1. -1 represents the case where soldYesterday is greater than soldToday; 1 represents the case where soldYesterday is not greater than soldToday.

Back 31

if (soldYesterday > soldToday)

salesTrend = -1;

else

salesTrend = 1;

Front 32

A String variable , fullName, contains a name in one of two formats:

last name , first name (comma followed by a blank), or

first name last name (single blank)

Extract the first name into the String variable firstName and the last name into the String variable lastName. Assume the variables have been declared and fullName already initialized . You may also declare any other necessary variables .

Back 32

int a = 0;

a = fullName.indexOf(",");

int b = 0;

b = fullName.indexOf(" ");

if (a > 0)

{

lastName = fullName.substring(0,a);

firstName = fullName.substring(a+2,fullName.length());

}

else

{

firstName = fullName.substring(0,b);

lastName = fullName.substring(b+1,fullName.length());

}

Front 33

20933: Clunker Motors Inc. is recalling all vehicles in its Extravagent line from model years 1999-2002. Given a variable modelYear and a String modelName write a statement that prints the message “RECALL” to standard output if the values of modelYear and modelName match the recall details.

Back 33

if (modelYear >= 1999 && modelYear <= 2002)

{

if (modelName == "Extravagant")

System.out.println("RECALL");

}

Front 34

Online Book Merchants offers premium customers 1 free book with every purchase of 5 or more books and offers 2 free books with every purchase of 8 or more books. It offers regular customers 1 free book with every purchase of 7 or more books, and offers 2 free books with every purchase of 12 or more books. Write a statement that assigns freeBooks the appropriate value based on the values of the boolean variable isPremiumCustomer and the int variable nbooksPurchased.

Back 34

freeBooks = 0;

if (isPremiumCustomer == true)

{

if (nbooksPurchased >= 5) freeBooks = 1;

if (nbooksPurchased >= 8) freeBooks = 2;

}

else

if (isPremiumCustomer == false)

{

if (nbooksPurchased >= 7) freeBooks = 1;

if (nbooksPurchased >= 12) freeBooks = 2;

}

Front 35

20938: NOTE: in mathematics, the square root of a negative number is not real; in Java therefore, passing such a value to the square root functions returns a value known as NaN (not-a-number). Given a double variable named areaOfSquare, write the necessary code to read in a value, the area of some square, into areaOfSquare and print out the length of the side of that square. HOWEVER: if any value read in is not valid input, just print the message “INVALID”. ASSUME the availability ofa variable stdin, that references a Scanner object associated with standard input.

Back 35

areaOfSquare = stdin.nextDouble();

if (areaOfSquare < 0)

System.out.print("INVALID");

else

System.out.print(Math.sqrt(areaOfSquare));

Front 36

20939: NOTE: in mathematics, division by zero is undefined. So, in Java, division by zero is always an error. Given a int variable named callsReceived and another int variable named operatorsOnCall write the necessary code to read values into callsReceived and operatorsOnCall and print out the number of calls received per operator (integer division with truncation will do. HOWEVER: if any value read in is not valid input, just print the message “INVALID”. ASSUME the availability of a variable, stdin, that references a Scanner object associated with standard input.

Back 36

callsReceived = stdin.nextInt();

operatorsOnCall = stdin.nextInt();

if (operatorsOnCall == 0)

System.out.print("INVALID");

else

System.out.print(callsReceived/operatorsOnCall);

Front 37

20940: Given a int variable named yesCount and another int variable named noCount and an int variable named response write the necessary code to read a value into response and then carry out the following: if the value tyoped in is a 1 or a 2 then increment yesCount and print out “YES WAS RECORDED”. if the value typed in is a 3 or a 4 then increment noCount and print out “NO WAS RECORDED” If the input is invalid just print the message “INVALID” and do nothing else. ASSUME the availability of a variable, stdin, that references a Scanner object associated with standard input.

Back 37

response = stdin.nextInt();

if (response == 1 || response == 2)

{

yesCount++;

System.out.print("YES WAS RECORDED");

}

else if (response == 3 || response == 4)

{

noCount++;

System.out.print("NO WAS RECORDED");

}

else

System.out.print("INVALID");

Front 38

20936: Clunker Motos Inc. is recalling all vehicles in its Extravagant line from model years 1999-2002 as well as all vehicles in its Guzzler line from model years 2004-2007. A boolean variable named recalled has been declared. Given a variable modelYear and a String modelName write a statement that assigns true to recalled if the values of modelYear and modelName match the recall details and assigns false otherwise.

Back 38

if ((modelYear >= 1999 && modelYear <= 2002 && modelName == "Extravagant")||(modelYear >= 2004 && modelYear <=2007 && modelName == "Guzzler"))

{

recalled = true;

}

else

recalled = false;

Front 39

20599: Write an expression that evaluates to true if the value of the string variable s1 is greater than the value of string variable s2.

Back 39

(s1.compareTo(s2)>0)

Front 40

20600: Write an expression that evaluates to true if the value of variable lastName is greater than the string Dexter.

Back 40

(lastName.compareTo("Dexter")>0)

Front 41

20603: Given the string variables name1, name2, and name3, write a fragment of code that assigns the largest value to the variable max (assume all three have already been declared and have been assigned values).

Back 41

if (name1.compareTo(name2)>0)

max = name1;

else

max = name2;

if (name3.compareTo(max)>0)

max = name3;

Front 42

20965: Assume that s is a String. Write an expression whose value is true if and only if the value of s would come between “mortgage” and “mortuary” in the dictionary.

Back 42

(s.compareTo("mortgage")>0) && (s.compareTo("mortuary")<0)

Front 43

60114: Difference in UNICODE value between ‘e’ and ‘a’

Difference in UNICODE value between ‘3’ and ‘0’

Back 43

4

3

Front 44

20902: Assume that x is a char variable that has been declared and already given a value. Write an expression whose value is true if and only if x is NOT a upper-case letter.

Back 44

!(x>='A' && x<='Z')

Front 45

20901: Assume that x is a char variable that has been declared and already given a value. Write an expression whose value is true if and only if x is an hexadecimal (Base 16) digit (0-9 plus A-F or a-f).

Back 45

(( x>='0' && x<='9') || ( x>='a' && x<='f' ) || ( x>='A' && x<='F'))

Front 46

20924: Assume that credits is an int variable whose value is 0 or positive. Write an expression whose value is “freshman” or “sophomore” or “junior” or “senior” based on the value of credits. In particular, if the value of credits is less than 30, the expression’s value is “freshman”; 30-59 would be a “sophomore”, 60-89 would be “junior” and 90 or more would be a “senior”.

Back 46

(credits < 30) ? "freshman" : (credits >= 30 && credits < 60) ?"sophomore" : (credits >= 60 && credits < 90) ? "junior" : "senior"

Front 47

20923: Assume that month is an int variable whose value is 1 or 2 or 3 or 5 … or 11 or 12. Write an expression whose value is “jan” or “feb” or “mar” or “apr” or “may” or “jun” or “jul” or “aug” or “sep” or “oct” or “nov” or “dec” based on the value of month. (So, if the value of month were 4, then the value of the expression would be “apr”.).

Back 47

(month==1) ? "jan" : (month==2) ? "feb" : (month==3) ? "mar" : (month==4) ? "apr" : (month==5) ? "may" : (month==6) ? "jun" : (month==7) ? "jul" : (month==8) ? "aug" : (month==9) ? "sep" : (month==10) ? "oct" : (month==11) ? "nov" : "dec"

Front 48

20623: Write a switch statement that texts the value of the char variable response and performs the following actions: if response is y, the message Your request is being processed is printed. if response is n, the message Thank you anyway for your consideration is printed. if response is h, the message Sorry no help is currently available is printed. for any other value of response, the message Invalid entry; pleas try again is printed.

Back 48

switch ( response )

{

case 'y':

System.out.println( "Your request is being processed");

break;

case 'n':

System.out.println( "Thank you anyway for your consideration");

break;

case 'h':

System.out.println( "Sorry, no help is currently available");

break;

default:

System.out.println( "Invalid entry; please try again");

}

Front 49

20926: HTTP is the protocol that governs communications between web servers and web clients (i.e. browsers). Part of the protocol includes a status code returned by the server to tell the browser the status of its most recent page request. Some of the codes and their meanings are listed below: 200, OK (fulfilled); 403, forbidden; 404, not found; 500, server error. Given an int variable status, write a switch statement that prints out, on a line by itself, the appropriate label from the above list based on status.

Back 49

switch (status)

{

case 200:

System.out.println("OK (fulfilled)");

break;

case 403:

System.out.println("forbidden");

break;

case 404:

System.out.println("not found");

break;

case 500:

System.out.println("server error");

break;

}