Chapter 3
Variables, Data Types, and Arithmetic Expressions
Exercises
1.
Type in and run the five programs presented in this chapter.
2.
List which of the following are invalid variables names, and why.
Answer:
char // Keyword for a type in C
6_05 // Variable names cannot start with a digit
A$ // Variable names must be alphanumeric
3.
List which of the following are invalid constants, and why.
Answer:
// Useful resource: https://www.eecis.udel.edu/~breech/progteam/contests/one-on-one-fall99.1/valid-c-const.html
0096 // Octal constants can only contain integers between 0 and 7
0x10.5 // Hexadecimal floats require a exponent (e.g. 0x10.5p2 where 0x is a prefix indicating a hexadecimal value, 10.5 is the significand, and p2 indicates 10 to the power of 2)
98.7U // Invalid suffix U on a floating constant
1.2Fe-7 // Invalid suffix Fe-7 on a floating constant (1.2e-7 would be valid, don't need a F suffix on a literal floating constant)
0X0G1 // Hexadecimal integer can only include characters from A - F
17777s // An integer can only be followed by the suffix' u, U, l, or L
15,000 // No commas are allowed in a integer
4.
Write a program that converts 27® from degrees Fahrenheit (F) to degrees Celsius (C).
5.
Write down the expected output from the following program.
Answer:
d = d
6.
Write a program to evaluate the polynomial 3x3 - 5x2 + 6.
7.
Write a program that evaluates the expression (3.31 x 10^-8 x 2.01 x 10^-7) / (7.16 x 10^-6 + 2.01 x 10^-8) and displays the results.
8.
For the next exercise, use the following formula to find the largest even multiple of i when divided by j:
Next_multiple = i + j - i % j
9.
Write a program to find the next largest even multiple for the following values of i and j:
| i | j |
|---|---|
| 365 | 7 |
| 12,258 | 23 |
| 996 | 4 |