Thread: postfix in array index

a would be assigned the value in element 3. ind would only then be incrememented.

However... it important to understand one thing; When is ind really incremented?

You have to understand what lvalues and rvalues are.

Shortly, an lvalue is an expression that can appear both in the left and the right side of an assigment. While a rvalue can only appear on the right-hand side of an assignment.

Code:

int a = 12;    // a is an lvalue. 12 is a rvalue. You cannot write 12 = a;
int b = a;       // b and a are lvalues. a, being an lvalue, can also be used on the right-hand side.
int c = a + b * 12;    // The expression a + b * 12 yields a rvalue. You cannot write a + b *12 = c;

So the big difference is this...

A prefixed increment or decrement operator (++ind) yields a lvalue as a result. It returns the object itself after applying the operator.

A postfixes increment or decrement operator (ind++) yields a rvalue. It returns a copy of the unchanged value of the object before it was incremented.

Both prefix and suffix versions of ind you have, happen when ind is being evaluated. However what is really different is what is returned from them.