|
ECS 30A |
Homework
#3 |
Fall 2008 |
Due: Monday, October 20.
Written: 4:00pm
in 2131 Kemper.
Programs: 11:59pm using handin to cs30a, p2 directory.
Filenames: car.c, projectile.c,
round.c earth.c, music.c, compass.c, gas.c, boiling.c
Written: p. 140: 1, 2, 3, 4, 5.
p.202: 5, 6
Programming:
All programs should be able to compile with no warnings when compiled with the
–Wall option. You should put your name(s) in a comment on the first line of
each file. The prompts and output format
of each program must match the following examples exactly. The actual values calculated by the programs
may vary slightly from the examples. To
use functions from math.h, you must have –lm on your compile line (that is an
“l” as in library) to link with the math library, e.g., gcc –Wall –lm car.c.
#1. (p. 140) Filename: car.c
[…@pc…]$ car.out
Please enter the principal,
and interest> 10000 18
Please enter the number of
payments> 36
Your loan of $10000.00 will
have monthly payments of $361.52.
[…@pc…]$
#4 (p. 141) Filename: projectile.c
[…@pc…]$ projectile.out
This program computes the
duration of a projectile's flight,
and its height above the
ground when it reaches the target.
The program will ask you for
the angle of elevation (in radians),
the distance to the target
(in feet), and the project velocity
(in feet per second).
Please enter the angle,
distance, velocity> 0.3 11000 800
The projectile will take
14.393 seconds to reach the target.
The projectile will hit the
target at a height of 70.6 feet.
[…@pc…]$
#5 ( p. 142) Filename: round.c
This can be done without calling any functions.
[…@pc…]$ round.out
Please enter a positive
number> 32.4851
That rounded is 32.4900
[…@pc…]$
#10 (p. 143) Filename earth.c
celsius should be an int, and Fahrenheit should be a double.
[…@pc…]$ earth.out
Please enter a depth (in
kilometers)> 25.9
The temperature at that
depth is 278 Celsius, or 532.4 Fahrenheit.
[…@pc…]$
#1. p 203 Filename: music.c
You should write this program without using an “else”.
The tricky part of this program is the need to transform the
money into ints to guarantee correct arithmetic of the displayed tax and
discount with the total purchases. You
should convert the double purchases to an int containing the corresponding
value in terms of cents. Note that
rounding errors cause 100 * 24.90 to become 2489 when storing in an int! You will need to add 0.1 to overcome the
rounding problem, e.g. 100 * 24.90 + 0.1 becomes 2490.
[…@pc…]$ music.out
Please enter your total
purchases> 122.00
Are you a teacher (0 = No, 1
= Yes)> 0
Total purchases $122.00
Sales tax (5%) 6.10
Total $128.10
[…@pc…]$ music.out
Please enter your total
purchases> 122.00
Are you a teacher (0 = No, 1
= Yes)> 1
Total purchases $122.00
Teacher's discount
(12%) 14.64
Discounted total 107.36
Sales tax (5%) 5.37
Total $112.73
[…@pc…]$
#3, p. 204 Filename: compass.c
North is 0°, East is 90°, South is 180°, and West is 270°.
[…@pc…]$ compass.out
Please enter a heading in degrees (0-360.0)> 23.3
That is North 23.3 East.
[…@pc…]$ compass.out
Please enter a heading in degrees (0-360.0)>
110.0
That is South 70.0 East.
[…@pc…]$ compass.out
Please enter a heading in degrees (0-360.0)> 370
Your heading is outside the allowed values.
Please try again.
[…@pc…]$
#4. p. 204 Filename: gas.c
You must use a switch statement.
[…@pc…]$ gas.out
Please enter the first letter of the cylinder's
color> O
Contents is ammonia.
[…@pc…]$ gas.out
Please enter the first letter of the cylinder's
color> y
Contents is hydrogen.
[…@pc…]$ gas.out
Please enter the first letter of the cylinder's
color> B
Contents is carbon monoxide.
[…@pc…]$
#11. p.207 Filename:
boiling.c
[…@pc…]$ boiling.out
Please enter the boiling point of the substance>
103
Substance is water.
[…@pc…]$ boiling.out
Please enter the boiling point of the substance>
1200
Substance is copper.
[…@pc…]$ boiling.out
Please enter the boiling point of the substance>
2500
Substance unknown.
[…@pc…]$