CODE DRILL 1 · RUN ONLY
This is a scratch drill — your code runs, nothing is graded or recorded. No test cases, no expected output, no verdict.
TASK
Write the recursive return for sum so that sum(0) returns 0 and each other call adds its current n to sum(n - 1). Print sum(4), which must produce 10.
OUTPUT
Sample10
What a finished answer prints, from the lesson. Nothing has run yet — press Run and this is replaced by your program’s own output.