This Python program calculates the sum of the squares of a list of numbers. There are multiple ways to accomplish this.

Method 1: Using a for Loop

This method defines a function sum_of_squares that iterates through a list, squares each number (including negative numbers), and adds it to a running total, which is then returned.

def sum_of_squares(numbers):
    total = 0
    for num in numbers:
        total += num ** 2
    return total

# Example 1:
my_numbers1 = [1, 2, 3, 4, 5]
result1 = sum_of_squares(my_numbers1)
print(f"The list of numbers is: {my_numbers1}")
print(f"The sum of their squares is: {result1}")
# Expected Output:
# The list of numbers is: [1, 2, 3, 4, 5]
# The sum of their squares is: 55

# Example 2 (with negative numbers):
my_numbers2 = [2, 10, -9, 78]
result2 = sum_of_squares(my_numbers2)
print(f"The list of numbers is: {my_numbers2}")
print(f"The sum of their squares is: {result2}")
# Expected Output:
# The list of numbers is: [2, 10, -9, 78]
# The sum of their squares is: 6269

Method 2: Using a Generator Expression

A more concise and "Pythonic" way to achieve the same result is by using a generator expression within Python's built-in sum() function. This approach generates the square of each number on-the-fly and sums them up in a single line of code.

# Example using a generator expression:
numbers = [1, 2, 10, -9, 78]
sum_of_squares = sum(x**2 for x in numbers)
print(f"The list of numbers is: {numbers}")
print(f"The sum of their squares is: {sum_of_squares}")
# Expected Output:
# The list of numbers is: [1, 2, 10, -9, 78]
# The sum of their squares is: 6270