30 lines
929 B
Markdown
30 lines
929 B
Markdown
> 1. If `i` is a variable and `p` points to `i`, which of the following expressions are aliases for `i`?
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a. `*p`
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g. `*&i`
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> 2. If `i` is an `int` variable and `p` and `q` are pointers to `int`, which of the following assignments are legal?
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e. `p = *&q;`
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f. `p = q;`
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i. `*p = *q`
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> 3. The following function supposedly computes the sum and average of the numbers in the array `a`, which has length `n`. `avg` and `sum` point to the variables that the function should modify, unfortunately the function contains several errors, find and correct them.
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```c
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void avg_sum(double a[], int n, double *avg, double *sum)
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{
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int i;
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// This was assigning a pointer to a float,
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// the dereference operator was missing
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*sum = 0.0;
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for (i = 0; i < n; i++)
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// This wasn't increasing the value
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// `sum` points to, it was modifying the address stored in the pointer
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(*sum) += a[i];
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// Missing dereference operators
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*avg = *sum / n;
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}
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``` |