C facts & stats

Question 1

Which character ends most statements in C?

Accepted Answer

Semicolon (;). C uses the semicolon as a statement terminator, so forgetting one is a classic compile error.

Question 2

In C, what is the index of the first element of an array?

Accepted Answer

0. C arrays are zero-indexed, so an array of 10 elements uses indexes 0 through 9.

Question 3

What does a pointer variable in C store?

Accepted Answer

A memory address. A pointer holds the location of another value, which you reach by dereferencing it.

Question 4

Which C operator gives the memory address of a variable?

Accepted Answer

&. Writing &x yields the address of x, which can then be stored in a pointer.

Question 5

Which format specifier prints a value of type int in decimal in C?

Accepted Answer

%d. %d prints a signed decimal integer, while %s is for strings, %f for floating-point and %c for characters.

Question 6

C was developed as a successor to which earlier language?

Accepted Answer

B. C grew out of a simpler, typeless language used on early Unix systems, adding data types and more.

Question 7

Which pair of standard library functions allocates and releases heap memory in C?

Accepted Answer

malloc and free. One requests a block of memory at runtime and the other returns it; forgetting to release memory causes leaks.

The basics