What does the arithmetic expression ((i<1?++i:--i)) do?

• A. If i is less than 1, increment i; otherwise decrement i.
• B. Always increments i.
• C. Always decrements i.
• D. Does nothing.

Answer: (A)

The expression uses the ternary conditional operator to pick between two pre-increment and pre-decrement operations based on whether i is less than 1. If i < 1 is true, it executes ++i, which increments i before its value is used. If i < 1 is false, it executes --i, which decrements i before its value is used. So the overall effect is: if i is less than 1, i is incremented; otherwise i is decremented. The value of the expression is the new i after that operation. For example, starting with i = 0 yields i = 1; starting with i = 2 yields i = 1.