Source Code

import re

def main():
    print("Welcome to the Main Function")
    print("Menu")
    print("E1 - Example 1")
    print("Q  - Quit")
    choice = input("Choice: ")
    match choice:
        case "E1":
            example1()
        case "E2":
            example2()
        case "E3":
            example3()
        case "E4":
            example4()
        case "E5":
            example5()
        case "E6":
            example6()
        case "E7":
            example7()
        case "E8":
            example8()
        case "E9":
            example9()
        case "E10":
            example10()
        case "E11":
            example11()
        case "E12":
            example12()
        case "Q":
            print("Quitting!")
        # default case
        case _:
            print("Invalid, try again!")

# define Example 1 Function
def example1():
    print("Example 1")
    university = "Kean"
    # version 1
    print("Index\tCharacter")
    for i in range(len(university)):
        print(str(i) + "\t" + university[i])

    # version 2
    for u in university:
        print(u)

    # first chararacter
    print("First Character: " + university[0])
    # last character
    print("Last Character: " + university[-1])

    # length of string
    print("Length: " + str(len(university)))
    print("Last Character: " + university[len(university)-1])

# define Example 2 Function
def example2():
    print("Example 2")
    text1 = "a b c d"
    words1 = text1.split()
    print(words1)
    text2 = "apple,banana,cherry,dragonfruit"
    words2 = text2.split(',')
    print(words2)

# define Example 3 Function
def example3():
    print("Example 3")
    text = "Hello, World!"
    index = text.find("World!")
    print(index)

# define Example 4 Function
def example4():
    print("Example 4")
    sentence = "Repeat, repeat, and repeat again."
    search = "repeat"
    index = sentence.find(search)
    while index != -1:
        print("Found at index: " + str(index))
        index = sentence.find(search, index + 1)

# define Example 5 Function
def example5():
    print("Example 5")
    text = "Hello world!"
    result = re.match(r"Hello", text)
    if result:
        print("Match found:", result.group())
    else:
        print("No match found.")

# define Example 6 Function
def example6():
    print("Example 6")
    result = re.match(r"world", text)
    if result:
        print("Match found:", result.group())
    else:
        print("No match found.")

# define Example 7 Function
def example7():
    print("Example 7")
    text = "The cat sat on the mat."
    result = re.search(r"cat", text)
    if result:
        print("Match found:", result.group())
    else:
        print("No match found.")

# define Example 8 Function
def example8():
    print("Example 8")
    text = "My numbers are 42, 98, and 256."
    numbers = re.findall(r"\d+", text)
    print(numbers)

# define Example 9 Function
def example9():
    print("Example 9")
    text = "I like cats. Cats are cute."
    new_text = re.sub(r"[Cc]ats", "dogs", text)
    print(new_text)

# define Example 10 Function
def example10():
    print("Example 10")
    text = "apple, orange; banana  mango"
    fruits = re.split(r"[,; ]+", text)
    print(fruits)

# define Example 11 Function
def example11():
    print("Example 11")
    number = "123-456-7890"
    if re.fullmatch(r"\d{3}-\d{3}-\d{4}", number):
        print("Valid")
    else:
        print("Invalid")

# define Example 12 Function
def example12():
    print("Example 12")
    text = "Contact us at [email protected] or [email protected]."
    emails = re.findall(r"[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}", text)
    print(emails)

main()