# Let us make a simple string variable
greeting = 'Hello, world!'
print(greeting)

# Using double quotes instead of single quotes
city = "London"
print(city)

# What if your text has an apostrophe?
food = 'It is Jenny\'s cake.'
print(food)

# Multi-line strings can use triple quotes
story = '''Once upon a time,
there was a coder.
They loved Python.'''
print(story)

# Let us check what type our variable is
print(type(greeting))

# The first character has index 0
name = 'Python'
print('First letter:', name[0])

# Negative indexes count from the end
print('Last letter:', name[-1])

# Slicing means getting part of a string
language = 'javascript'
print(language[0:4])  # Get the first four letters

# Strings are immutable, which means you cannot change them in place
# You must make a new string if you want something different
pet = 'cat'
# pet[0] = 'b'  # This line would cause an error
animal = 'b' + pet[1:]
print(animal)

# .upper() turns all letters into uppercase
phrase = 'good morning'
print(phrase.upper())

# .replace() swaps old text for something new
cheer = 'hip hip hooray!'
new_cheer = cheer.replace('hip', 'yay')
print(new_cheer)

# .find() searches for where a string appears
sentence = 'Where is the cat?'
position = sentence.find('cat')
print('Cat starts at:', position)

# Getting user input and working with it
user_text = input('Type something fun: ')
upper_text = user_text.upper()
print('You in caps:', upper_text)

# Practice: Ask the user for their name, then greet them
name = input('What is your name? ')
print('Nice to meet you, ' + name + '!')

# Mini-Project Part 1: Counting words in a sentence
text = input('Give me a sentence: ')
words = text.split()
count = len(words)
print('Your sentence has ' + str(count) + ' words.')

# Mini-Project Part 2: Make initials from a full name
full_name = input('Enter your full name: ')
parts = full_name.strip().split()
initials = ''
for part in parts:
    initials += part[0].upper()
print('Your initials are: ' + initials)

# Helpful: Stripping extra spaces from text
raw = '  too much space!   '
fixed = raw.strip()
print('Before:', '[' + raw + ']')
print('After:', '[' + fixed + ']')

# Common mistake example: mixing numbers and strings
weight = 2
message = 'Your order weighs ' + str(weight) + ' pounds.'
print(message)