# Exercise 03: Trace rules and repetition

Use a copy of examples/03.

## A. Boundary predictions
For remaining values -1, 0 and 1, write the label each branch should choose. Why is checking zero before positive counts important?

## B. Repair
First predict what happens to the final outside-loop console.log if `let total = 0` is moved inside the for...of block. Run it and identify the ReferenceError caused by scope. To observe the reset separately, temporarily move the total log inside the loop after the addition: what does it print for [3, 0, 5]? Restore the declaration and final log outside the loop, then trace the correctly accumulated total.

## C. Transfer
Without copying the supplied loop, count how many values in [3, 0, 5, 0] are greater than zero. Your result should be 2. Add another positive value and confirm your code adapts without an extra repeated if statement.

## Evidence
An iteration trace with the accumulator after each step. Include one empty-array trial; its count should be zero.

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