Describe what this function does. Try different numbers as input.

Question

```
def test(num):
if num > 0:
return num – test(num-1)
else:
return 0
```

Answer 1

This method recursively calls itself with a decremented number, and subtracts that call from that number each time. This has an interesting effect, displayed in the examples below:

```
test(1) = 1
test(2) = 2-test(1) = 1
test(3) = 3-test(2) = 2
test(4) = 4-test(3) = 2
test(5) = 5-(test4) = 3
…
```