Python Program to Print Sum of Negative Numbers, Positive Even & Odd Numbers in a List

This Python program is designed to analyze a list of numbers and compute the sums of specific categories within that list. It categorizes the numbers into three groups: negative numbers, positive even numbers, and positive odd numbers. Subsequently, it calculates the sum for each category and prints out the results.

Problem Statement

You are tasked with creating a Python program that performs analysis on a list of integers.

Python Program to Print Sum of Negative Numbers, Positive Even & Odd Numbers in a List

def calculate_sums(numbers):
    sum_negative = 0
    sum_even = 0
    sum_odd = 0

    for num in numbers:
        if num < 0:
            sum_negative += num
        elif num % 2 == 0:
            sum_even += num
        else:
            sum_odd += num

    return sum_negative, sum_even, sum_odd

# Input list of numbers
numbers = [12, -7, 5, 64, -14]

# Calculate the sums
sum_negative, sum_even, sum_odd = calculate_sums(numbers)

# Print the results
print("Sum of negative numbers:", sum_negative)
print("Sum of positive even numbers:", sum_even)
print("Sum of positive odd numbers:", sum_odd)

How it works

The Python program provided calculates and prints the sum of negative numbers, positive even numbers, and positive odd numbers in a list. Here’s a step-by-step explanation of how it works:

1. Define the calculate_sums Function:
   • def calculate_sums(numbers):
   • This function is defined to calculate the sums. It takes a list of integers (numbers) as input.
2. Initialize Sum Variables:
   • sum_negative = 0 sum_even = 0 sum_odd = 0
   • Three variables (sum_negative, sum_even, and sum_odd) are initialized to keep track of the sums for negative numbers, positive even numbers, and positive odd numbers, respectively. These variables are initially set to 0.
3. Iterate Through the List:
   • for num in numbers:
   • The program uses a for loop to iterate through each number in the input list.
4. Categorize and Sum the Numbers:
   • if num < 0: sum_negative += num elif num % 2 == 0: sum_even += num else: sum_odd += num
   • For each number in the list, it checks whether the number is:
   • Negative: If yes, it adds the number to sum_negative.
   • Positive and even: If yes, it adds the number to sum_even.
   • Positive and odd: If yes, it adds the number to sum_odd.
5. Return the Sums:
   • return sum_negative, sum_even, sum_odd
   • The function returns the calculated sums as a tuple containing sum_negative, sum_even, and sum_odd.
6. Input List and Calculate Sums:
   • numbers = [12, -7, 5, 64, -14] sum_negative, sum_even, sum_odd = calculate_sums(numbers)
   • In the main part of the program, a list of numbers (numbers) is defined. The calculate_sums function is then called with this list as input, and the results are assigned to sum_negative, sum_even, and sum_odd.
7. Print the Results:
   • print("Sum of negative numbers:", sum_negative) print("Sum of positive even numbers:", sum_even) print("Sum of positive odd numbers:", sum_odd)
   • Finally, the program prints the results with clear labels, indicating the sum of negative numbers, the sum of positive even numbers, and the sum of positive odd numbers.
   • By following these steps, the program processes a list of numbers and categorizes them into the specified categories, calculating and printing the sums for each category.

Input/Output