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Unit 1 Session 1 (Click for link to problem statements)

U-nderstand

Understand what the interviewer is asking for by using test cases and questions about the problem.

• Do I need to modify the provided function?
  • No.

P-lan

Plan the solution with appropriate visualizations and pseudocode.

General Idea: Create a function to safely get the last element of a list.

1) Create a new function with a parameter for the list
2) If the list is not empty, look for the last element:
  a) Find the length of the list
  b) Get the element at index length - 1 
3) Otherwise, return None

⚠️ Common Mistakes

• Why would we look at index "length - 1" instead of just "length"?

I-mplement

# Could also do with looping and a temp variable instead of using len

def get_last(lst):
	if lst:
		length = len(lst)
		return lst[length - 1]
	else:
		return None