Python: Find the largest negative and smallest positive numbers

Last update on April 17 2025 13:02:41 (UTC/GMT +8 hours)

Largest Negative and Smallest Positive Numbers

Write a Python program to find the largest negative and smallest positive numbers (or 0 if none).

Input:  
[-12, -6, 300, -40, 2, 2, 3, 57, -50, -22, 12, 40, 9, 11, 18]
Output:
[-6, 2]

Input: 
[-1, -2, -3, -4]
Output:
[-1, 0]

Input: 
[1, 2, 3, 4]
Output:
[0, 1]

Input: 
[]
Output:
[0, 0]

Visual Presentation:

Python: Find the largest negative and smallest positive numbers.

Sample Solution:

Python Code:

# License: https://bit.ly/3oLErEI

# Define a function named 'test' that takes a list of numbers as input
def test(nums):
    # Create a list 'pos' containing positive numbers from the input list
    pos = [n for n in nums if n > 0]
    
    # Create a list 'neg' containing negative numbers from the input list
    neg = [n for n in nums if n < 0]
    
    # Return a list containing the largest negative number (or 0 if none) and the smallest positive number (or 0 if none)
    return [max(neg) if neg else 0, min(pos) if pos else 0]

# Example 1
nums1 = [-12, -6, 300, -40, 2, 2, 3, 57, -50, -22, 12, 40, 9, 11, 18]
print("List of numbers:", nums1)
print("Largest negative and smallest positive numbers (or 0 if none) of the said list:")
print(test(nums1))

# Example 2
nums2 = [-1, -2, -3, -4]
print("\nList of numbers:", nums2)
print("Largest negative and smallest positive numbers (or 0 if none) of the said list:")
print(test(nums2))

# Example 3
nums3 = [1, 2, 3, 4]
print("\nList of numbers:", nums3)
print("Largest negative and smallest positive numbers (or 0 if none) of the said list:")
print(test(nums3))

# Example 4
nums4 = []
print("\nList of numbers:", nums4)
print("Largest negative and smallest positive numbers (or 0 if none) of the said list:")
print(test(nums4))

Sample Output:

List of numbers: [-12, -6, 300, -40, 2, 2, 3, 57, -50, -22, 12, 40, 9, 11, 18]
Largest negative and smallest positive numbers (or 0 if none) of the said list:
[-6, 2]

List of numbers: [-1, -2, -3, -4]
Largest negative and smallest positive numbers (or 0 if none) of the said list:
[-1, 0]

List of numbers: [1, 2, 3, 4]
Largest negative and smallest positive numbers (or 0 if none) of the said list:
[0, 1]

List of numbers: []
Largest negative and smallest positive numbers (or 0 if none) of the said list:
[0, 0]

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to scan a list and return the largest negative and smallest positive numbers, using conditional filters.
Write a Python program to separate negatives and positives from a list, then output the maximum negative and minimum positive.
Write a Python program to use list comprehensions to extract negative and positive numbers and then select the required values.
Write a Python program to implement a single-pass algorithm that determines the largest negative and smallest positive numbers.

Go to:

Previous: Find the two closest distinct numbers in a given a list of numbers.
Next: Round each float in a list of numbers up to the next integer and return the running total of the integer squares.

Python Code Editor :

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