34 lines
1.4 KiB
Markdown
34 lines
1.4 KiB
Markdown
1. Suppose that the following declarations are in effect:....
|
|
a. `14`
|
|
b. `34`
|
|
c. `4`
|
|
d. `true`
|
|
e. `false`
|
|
|
|
2. Suppose that `high`, `low`, and `middle` are all pointer variables of the same type, and the `low` and `high` point to elements of an array. Why is the following statement illegal, and how could it be fixed?
|
|
```c
|
|
middle = (low + high) / 2
|
|
```
|
|
The above statement is illegal because you can't add an `int *` to an `int *`. The below operation is legal because you can perform pointer subtraction, and because `low` is defined on the left hand side of the equation, then adding a long to a pointer is valid.
|
|
```c
|
|
middle = low + (high - low) / 2;
|
|
```
|
|
|
|
3. What will be the contents of the `a` array after the following statements are executed?
|
|
```c
|
|
{10, 9, 8, 7, 6, 5, 4, 3, 2, 1}
|
|
```
|
|
|
|
5. Suppose that `a` is a one dimensional array and `p` is a pointer variable. assuming that the assignment `p = a` has just been performed, which of the following expressions are illegal because of mismatched types? Of the remaining expressions, which are true (have a nonzero value)?
|
|
The following expressions are illegal because of mismatched types:
|
|
- (a) `p == a[0]` - Comparison between `int *` and `int`
|
|
The rest of the expressions are true.
|
|
|
|
8. Rewrite the following function to use pointer arithmetic...
|
|
```c
|
|
void store_zeros(int *a, int n) {
|
|
for (int i = 0; i < n; i++) {
|
|
*(a + i) = 0;
|
|
}
|
|
}
|
|
``` |