Python: Compute the sum of the negative and positive numbers of an array of integers and display the largest sum

Last update on May 24 2025 10:48:44 (UTC/GMT +8 hours)

Sum of Positive and Negative

Write a Python program to compute the sum of the negative and positive numbers in an array of integers and display the largest sum.

Sample Solution

Python Code:

# Define a function 'test' that takes a list of numbers as input and returns the largest sum 
# among positive and negative numbers separately.
def test(lst):
    # Initialize variables to store the sum of positive and negative numbers.
    pos_sum = 0
    neg_sum = 0

    # Iterate through each number in the input list.
    for n in lst:
        # Check if the number is positive.
        if n > 0:
            pos_sum += n  # Add the positive number to the positive sum.
        # Check if the number is negative.
        elif n < 0:
            neg_sum += n  # Add the negative number to the negative sum.

    # Return the largest sum among positive and negative numbers using the 'max' function,
    # with 'key=abs' to consider the absolute values.
    return max(pos_sum, neg_sum, key=abs)

# Test cases with different sets of numbers.
nums = {0, -10, -11, -12, -13, -14, 15, 16, 17, 18, 19, 20}
print("Original array elements:")
print(nums)
print("Largest sum - Positive/Negative numbers of the said array: ", test(nums))

nums = {-11, -22, -44, 0, 3, 4, 5, 9}
print("\nOriginal array elements:")
print(nums)
print("Largest sum - Positive/Negative numbers of the said array: ", test(nums))

Sample Output:

Original array elements:
{0, 15, 16, 17, -14, -13, -12, -11, -10, 18, 19, 20}
Largest sum - Positive/Negative numbers of the said array:  105

Original array elements:
{0, 3, 4, 5, 9, -22, -44, -11}
Largest sum - Positive/Negative numbers of the said array:  -77

Explanation:

Here is a breakdown of the above Python code:

Define Test Function (test function):

The "test()" function takes a list of numbers as input.
It initializes variables 'pos_sum' and 'neg_sum' to store the sum of positive and negative numbers, respectively.
It iterates through each number in the input list, updating the sums accordingly.
The function returns the largest sum among positive and negative numbers using the max function with key=abs to consider absolute values.

Flowchart:

Flowchart: Python - Find all the factors of a given natural number.

For more Practice: Solve these Related Problems:

Write a Python program to compute the sum of positive numbers and negative numbers separately from a list and return the larger sum.
Write a Python program to partition a list into positive and negative numbers, sum each group, and output the greater total.
Write a Python program to calculate two separate sums from a list (one for positives, one for negatives) and compare them.
Write a Python program to iterate over an array, summing positive and negative numbers individually, then display the higher sum.

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Python Code Editor:

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