Chapter 03 Checkpoints Flashcards
3.1 What header le must be included in programs using cin?
3.1
iostream
3.2 TRUE or FALSE: cin requires the user to press the [Enter] key when finished
entering data.
3.2 True
3.3 Assume value is an integer variable. If the user enters 3.14 in response to the following
programming statement, what will be stored in value?
cin»_space; value;
A) 3.14
B) 3
C) 0
D) Nothing. An error message is displayed.
3.3 B
3.4 A program has the following variable de nitions.
long miles;
int feet;
float inches;
Write one cin statement that reads a value into each of these variables.
3.4
cin»_space; miles»_space; feet»_space; inches;
3.5 The following program will run, but the user will have dif culty understanding
what to do. How would you improve the program?
// This program multiplies two numbers and displays the result.
#include
using namespace std;
int main()
{
double first, second, product;
cin»_space; first»_space; second;
product = first * second;
cout
3.5 Include one or more
cout
statements explaining what values the user should enter.
3.6 Complete the following program skeleton so it asks for the user s weight (in
pounds) and displays the equivalent weight in kilograms.
#include
using namespace std;
int main()
{
double pounds, kilograms;
// Write code here that prompts the user
// to enter his or her weight and reads
// the input into the pounds variable.
// The following line does the conversion.
kilograms = pounds / 2.2;
// Write code here that displays the user’s weight
// in kilograms.
return 0;
}
3.6
#include
using namespace std;
int main()
{
double pounds, kilograms;
cout > pounds;
// The following line does the conversion.
// One kilogram weighs 2.2 pounds.
kilograms = pounds / 2.2;
cout3.7 Complete the table below by writing the value of each expression in the Value
column.
Expression Value 6 + 3 * 5 12 / 2 - 4 9 + 14 * 2 - 6 5 + 19 % 3 - 1 (6 + 2) * 3 14 / (11 - 4) 9 + 12 * (8 - 3) (6 + 17) % 2 - 1 (9 - 3) * (6 + 9) / 3
3.7 Value 21 2 31 5 24 2 69 0 30
3.8 Write C++ expressions for the following algebraic expressions:
y = 6x a = 2b + 4c y x2 = g x + 2 z2 = ------------ y x2 z2 = -----
3.8 y = 6 * x; a = 2 * b + 4 * c; y = x * x; or y = pow(x, 2.0); g = (x + 2) / (z * z); or g = (x + 2.0) / pow(z, 2.0); y = (x * x) / (z * z); or y = pow(x, 2.0) / pow (z, 2.0);
3.9 Study the following program and complete the table.
#include
#include
using namespace std;
int main()
{
double value1, value2, value3;
cout > value1;
value2 = 2 * pow(value1, 2.0);
value3 = 3 + value2 / 2 - 1;
cout3.9 If the user enters… The program displays… 2 6 5 27 4.3 20.49 6 38
Complete the following program skeleton so it displays the volume of a cylindrical
fuel tank. The formula for the volume of a cylinder is
Volume = r2h
where
is 3.14159
r is the radius of the tank
h is the height of the tank
#include
#include
using namespace std;
int main()
{
double volume, radius, height;
cout > height;
cout > radius;
// You must complete the program.
}3.10
#include
#include
using namespace std;
int main()
{
double volume, radius, height;
cout > height;
cout > radius;
volume = 3.14159 * pow(radius, 2.0) * height;
cout
3.11 Assume the following variable de nitions: int a = 5, b = 12; double x = 3.4, z = 9.1; What are the values of the following expressions? A) b / a B) x * a C) static_cast(b / a) D) static_cast(b) / a E) b / static_cast(a) F) static_cast(b) / static_cast(a) G) b / static_cast(x) H) static_cast(x) * static_cast(z) I) static_cast(x * z) J) static_cast(static_cast(x) * static_cast(z))
3.11 A) 2 B) 17.0 C) 2.0 D) 2.4 E) 2.4 F) 2.4 G) 4 H) 27 I) 30 J) 27.0
3.12 Complete the following program skeleton so it asks the user to enter a character.
Store the character in the variable letter. Use a type cast expression with the variable
in a cout statement to display the character s ASCII code on the screen.
#include
using namespace std;
int main()
{
char letter;
// Finish this program
// as specified above.
return 0;
}3.12
#include
using namespace std;
int main()
{
char letter;
cout > letter;
cout3.13 What will the following program display?
#include
using namespace std;
int main()
{
int integer1, integer2;
double result;
integer1 = 19;
integer2 = 2;
result = integer1 / integer2;
cout3.13 9
9.5
9
3.14 Write a multiple assignment statement that assigns 0 to the variables total,
subtotal, tax, and shipping.
3.14
total = subtotal = tax = shipping = 0;
3.15 Write statements using combined assignment operators to perform the following:
A) Add 6 to x.
B) Subtract 4 from amount.
C) Multiply y by 4.
D) Divide total by 27.
E) Store in x the remainder of x divided by 7.
F) Add y * 5 to x.
G) Subtract discount times 4 from total.
H) Multiply increase by salesRep times 5.
I) Divide profit by shares minus 1000.
3.15 A) x += 6; B) amount -= 4; C) y *= 4; D) total /= 27; E) x %= 7; F) x += (y * 5); G) total -= (discount * 4); H) increase *= (salesRep * 5); I) profit /= (shares – 1000);
3.16 What will the following program display?
#include
using namespace std;
int main()
{
int unus, duo, tres;
unus = duo = tres = 5;
unus += 4;
duo *= 2;
tres -= 4;
unus /= 3;
duo += tres;
cout3.16
3
11
1
3.17 Write cout statements with stream manipulators that perform the following:
A) Display the number 34.789 in a eld of nine spaces with two decimal places
of precision.
B) Display the number 7.0 in a eld of ve spaces with three decimal places of
precision.
The decimal point and any trailing zeroes should be displayed.
C) Display the number 5.789e+12 in xed point notation.
D) Display the number 67 left justi ed in a eld of seven spaces.
3.17 A)
cout
3.18 The following program will not compile because the lines have been mixed up.
#include
}
cout
3.18
#include
#include
using namespace std;
int main()
{
string person = "Wolfgang Smith";
cout3.19 The following program skeleton asks for an angle in degrees and converts it to
radians. The formatting of the nal output is left to you.
#include
#include
using namespace std;
int main()
{
const double PI = 3.14159;
double degrees, radians;
cout > degrees;
radians = degrees * PI / 180;
// Display the value in radians left justified, in fixed
// point notation, with 4 places of precision, in a field
// 5 spaces wide, making sure the decimal point is always
// displayed.
return 0;
}
3.19
#include
#include
using namespace std;
int main()
{
const double PI = 3.14159;
double degrees, radians;
cout > degrees;
radians = degrees * PI / 180;
cout3.20 Write a short description of each of the following functions:
cos log sin
exp log10 sqrt
fmod pow tan
3.20
cos
: Returns the cosine of the argument.
exp
: Returns the exponential function of the argument.
fmod
: Returns the remainder of the first argument divided by the second argument.
log
: Returns the natural logarithm of the argument.
log10
: Returns the base-10 logarithm of the argument.
pow
: Returns the value of the first argument raised to the power of the second
argument.
sin
: Returns the sine of the argument.
sqrt
: Returns the square root of the argument.
tan
: Returns the tangent of the argument.
3.21 Assume the variables angle1 and angle2 hold angles stored in radians. Write a
statement that adds the sine of angle1 to the cosine of angle2, and stores the
result in the variable x.
3.21
x = sin(angle1) + cos(angle2);
3.22 To nd the cube root (the third root) of a number, raise it to the power of 1
3. To
nd the fourth root of a number, raise it to the power of 1
4. Write a statement
that will nd the fth root of the variable x and store the result in the variable y.
3.22
y = pow(x, 0.2); // 0.2 is equal to 1/5
3.23 The cosecant of the angle a is
Write a statement that calculates the cosecant of the angle stored in the variable a,
and stores it in the variable y.
3.23
y = 1 / sin(a);
