Find the Second-Largest Number

[Mr-Glucose]

Description

Write a function to find the second-largest number in a list of integers. Return None if the list has fewer than two unique numbers.

Requirements

• Input will always be a list of integers.
• Handle cases with duplicate numbers appropriately (e.g., [4, 4, 3, 2] should return 3).

Example

find_second_largest([1, 2, 3, 4]) 
# Output: 3

find_second_largest([4, 4, 3, 2]) 
# Output: 3

find_second_largest([10]) 
# Output: None

Testing

Develop tests to validate your function. Consider:

• Lists with duplicate values.
• Lists with fewer than two unique numbers.
• Large lists with mixed positive and negative integers.

Helpful Links

• Python Sorting
• Python Sets