Arrays Questions and Answers

Answer: B

Correct answer: 1, 2

The name of an array normally decays to the address of its first element - which is why passing it to scanf() or printf() gives the base address. There are two exceptions. With sizeof the name means the whole array, so sizeof(arr) gives the total number of bytes. With & it again means the whole array, so &arr has type “pointer to array”. Those are statements 1 and 2.

Answer: B

Correct answer: 2

Build the max-heap bottom-up, checking each internal node from the last one back to the root. Numbering the array from 1:

1:89  2:19  3:40  4:14  5:17  6:12  7:10  8:2  9:5  10:7  11:11  12:6  13:9  14:70

• Node 7 holds 10 with the single child 70 - swap. Node 7 now holds 70.
• Nodes 6, 5 and 4 already dominate their children (12 over 6 and 9; 17 over 7 and 11; 14 over 2 and 5).
• Node 3 holds 40 with children 12 and 70 - swap with 70. The 40 that sinks to node 7 still beats its only child, 10.
• Node 2 (19 over 14 and 17) and the root (89 over 19 and 70) are already correct.

That is 2 interchanges in all.

Answer: B

Correct answer: All the above

The size may be left out in all three cases. In a definition with an initialiser, int a[] = {1,2,3};, the compiler counts the initialisers. In a formal parameter, void f(int a[]), the array is adjusted to a pointer and any bound is ignored. In a declaration, extern int a[];, the definition elsewhere supplies the size.

Answer: B

Correct answer: Dope vector

A dope vector is the run-time descriptor of an array: base address, element size, number of dimensions and the bounds of each. It is what makes address computation, and bounds checking in languages that do it, possible. A symbol table is a compile-time structure of names and types; an activation record holds one call’s local storage.