Question

I have the following code:

enum e {
    X=1,
    Y,
    Z
}

What will be the values of enum elements if the first one is defined to 1?

Will the other elements be incremented by 1 each one?

Answer 1

As everyone else is saying, the answer is yes. Here’s the standard’s way of saying that.

C99 Specification. Section 6.7.2.2 Enumeration specifiers. Paragraph 3

The identifiers in an enumerator list are declared as constants that have type int and may appear wherever such are permitted.) An enumerator with = defines its enumeration constant as the value of the constant expression. If the first enumerator has no =, the value of its enumeration constant is 0.

Each subsequent enumerator with no = defines its enumeration constant as the value of the constant expression obtained by adding 1 to the value of the previous enumeration constant. (The use of enumerators with = may produce enumeration constants with values that duplicate other values in the same enumeration.)

The enumerators of an enumeration are also known as its members.