write a loop that reads positive integers from standard input and that terminates when it reads an integer that is not positive

write a loop that reads positive integers from standard input and that terminates when it reads an integer that is not positive. After the loop terminates, it prints out, ona line by itself, the sum of all even integers read. a while loop and python is required to do the question
write a loop that reads positive integers from standard input and that terminates when it reads an integer that is not positive. After the loop terminates, it prints out, ona line by itself, the sum of all even integers read.

a while loop and python is required to do the question

The Correct Answer and Explanation is :

To solve the problem of reading positive integers from standard input and calculating the sum of all even integers, we can utilize a while loop in Python. The loop will continue to prompt the user for input until a non-positive integer is entered, at which point it will terminate and display the sum of all even integers entered.

Here’s the Python code to achieve this:

# Initialize the sum of even integers
even_sum = 0

# Start an infinite loop to read user input
while True:
    # Prompt the user for input and convert it to an integer
    user_input = int(input("Enter a positive integer (or a non-positive integer to stop): "))

    # Check if the input is positive
    if user_input <= 0:
        # If not positive, break the loop
        break
    # Check if the input is even
    elif user_input % 2 == 0:
        # Add the even number to the sum
        even_sum += user_input

# After the loop ends, print the sum of even integers
print(f"The sum of all even integers entered is: {even_sum}")

Explanation:

Initialization: We start by initializing a variable even_sum to zero. This variable will accumulate the sum of all even integers entered by the user.
Infinite Loop: We use a while True loop to continuously prompt the user for input. This loop will run indefinitely until a non-positive integer is entered.
User Input: Inside the loop, we prompt the user to enter a positive integer. The input() function reads the input as a string, and int() converts it to an integer.
Input Validation: We check if the entered integer is positive:

If the integer is less than or equal to zero, we use the break statement to exit the loop.
If the integer is positive and even (i.e., user_input % 2 == 0), we add it to even_sum.

Termination and Output: Once the loop terminates (i.e., a non-positive integer is entered), we print the accumulated sum of even integers.

Example Run:

Enter a positive integer (or a non-positive integer to stop): 4
Enter a positive integer (or a non-positive integer to stop): 7
Enter a positive integer (or a non-positive integer to stop): 10
Enter a positive integer (or a non-positive integer to stop): -1
The sum of all even integers entered is: 14

In this example:

The user enters 4, which is even, so it’s added to even_sum (now 4).
The user enters 7, which is odd, so it’s ignored.
The user enters 10, which is even, so it’s added to even_sum (now 14).
The user enters -1, which is non-positive, causing the loop to terminate.

Key Points:

while True Loop: This construct creates an infinite loop that continues until explicitly broken. It’s useful when the number of iterations isn’t known in advance and depends on user input.
input() and int(): The input() function reads user input as a string. Using int() converts this string to an integer, allowing numerical operations.
break Statement: This statement exits the loop immediately, which is essential for terminating the loop when a non-positive integer is entered.
Modulo Operator (%): The expression user_input % 2 == 0 checks if the number is even. If the remainder when divided by 2 is zero, the number is even.

This approach ensures that the program efficiently reads and processes user input, calculating the sum of even integers until a non-positive integer is encountered.

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