##### Short Problem Definition:

Brie’s Drawing teacher asks her class to open their books to a page number. Brie can either start turning pages from the front of the book or from the back of the book. She always turns pages one at a time.

##### Link

##### Complexity:

time complexity is `O(1)`

space complexity is `O(1)`

##### Execution:

Think of this as a 0-indexed book. Use integer division.

##### Solution:

```
def solve(n, p):
last_letter = n // 2
goal_letter = p // 2
return min(goal_letter, last_letter-goal_letter)
```