**Note**: If you wish to meet with me one on one to discuss the course, please shoot me an email with your available times. My email can be found on the course info page.

# Question 1

Draw the environment diagram.

```
def reverse(lst):
if len(lst) <= 1:
return lst
return reverse(lst[1:]) + [lst[0]]
l = [1, [2, 3], 4]
rev = reverse(l)
```

**Followup**: How would you modify this to *deep-reverse* a list - that is, if an element of the list is also a list, that element gets reversed as well (and all lists under it)?

# Question 2

What does the following code print?

```
lst = [None for _ in range(10)]
for i in range(10):
lst[i] = lambda: i
for func in lst:
print(func())
```

# Question 3

Implement a function `addup`

that takes in a `lst`

of numbers and a target value `n`

. It should return `True`

if some subset of `lst`

adds up to `n`

. Numbers in `lst`

may not be reused. For example:

```
>>> addup([3, 4, 5], 9)
True # 4 + 5 = 9
>>> addup([3, 9, 27, 81], 3)
True # 3 = 3
>>> addup([3, 9, 27, 81], 33)
False
```

**Followup**: What needs to be changed if values in `lst`

can be reused?