Python: Rearrange positive and negative numbers in a given array using Lambda

Last update on April 22 2025 12:52:10 (UTC/GMT +8 hours)

12. Rearrange Pos/Neg Lambda

Write a Python program to rearrange positive and negative numbers in a given array using Lambda.

Sample Solution:

Python Code :

# Define a list 'array_nums' containing both positive and negative integers
array_nums = [-1, 2, -3, 5, 7, 8, 9, -10]

# Display a message indicating that the following output will show the original array
print("Original arrays:")
print(array_nums)  # Print the contents of 'array_nums'

# Use the 'sorted()' function to rearrange the elements in 'array_nums' based on a custom key
# The 'key' parameter uses a lambda function to sort the elements:
#   - It places positive numbers before negative numbers and zeros, maintaining their original order
#   - Zeros are placed at the front (index 0) of the sorted list
result = sorted(array_nums, key=lambda i: 0 if i == 0 else -1 / i)

# Display the rearranged array where positive numbers come before negative numbers and zeros
print("\nRearrange positive and negative numbers of the said array:")
print(result)  # Print the rearranged 'result' array.

Sample Output:

Original arrays:
[-1, 2, -3, 5, 7, 8, 9, -10]

Rearrange positive and negative numbers of the said array:
[2, 5, 7, 8, 9, -10, -3, -1]

For more Practice: Solve these Related Problems:

Write a Python program to rearrange an array so that all even numbers appear before the odd numbers using lambda.
Write a Python program to rearrange an array so that numbers divisible by 3 come first using lambda.
Write a Python program to rearrange an array such that prime numbers are positioned at the beginning using lambda.
Write a Python program to rearrange an array by alternating positive and negative numbers using lambda.

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Python Code Editor:

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