while True:
    try:
        numbers = input("Enter a series of numbers separated by spaces: ")
        number_list = numbers.split()

        # Convert the list of strings to a list of integers
        number_list = [int(num) for num in number_list]

        # Calculate the sum of the numbers
        sum_of_numbers = sum(number_list)

        # Print the sum
        print("Sum of the numbers:", sum_of_numbers)
        break

    except ValueError:
        print("Invalid input. Please enter numbers separated by spaces. Try again.")