# sumnN(n) returns the sum of the first n natural numbers.
# sumNCubes(n) returns the sum of the cubes of the first n natural numbers.

# Then use these functions in a program that prompts a user for an n and prints out the sum of the first n natural numbers and the sub of the cubes of the first n natural numbers.

# What the heck is a natural number?
# number that is positive and whole

# Prompt function
def prompt():
    promptresponse = int(input("Please enter a number for n:"))
    return promptresponse

def sumN(n):
    sum = 0 #initialize sum for use
    print("Let's show the work for the sum of the natural numbers:\n")
    for i in range(1,n+1): # start building the natural numbers leading up to n.
        sum += i
        if sum != n+1:
            string_concatenate = f"{i} + " # concatenate the string to show the user the sum
        else:
            string_concatenate = f"{i}"
        print(string_concatenate, end="") # print the string
    print(f" = {sum}") # print the sum
    return sum # return the sum to the function
    
def sumNCubes(n):
    sum = 0 #initialize sum for use
    for i in range(1,n+1): # start building the natural numbers leading up to n.
        sum += i**3 # add the cube of the number to the sum
        if sum!=n+1:
            string_concatenate = f"{i}^3 + "
        else:
            string_concatenate = f"{i}^3"
        print(string_concatenate, end="") # print the string
    return sum # return the sum to the function
    
# Main Function
def main():
    # Prompt the user for n.
    n=prompt()
    print(f"The sum for sumN of the 'natural numbers is': {sumN(n)}")
    
    print(f"The sum for sumN of the 'natural numbers is': {sumNCubes(n)}")

    # Ask the user to see if they want to continue
    continueprompt = input("Would you like to continue? (y/n)")
    if continueprompt == "y":
        main()
    else:
        print("Goodbye!")
if __name__ == "__main__":
    main()