string interpolation example in python3

hello_world.py

'''
When you run this code it will generate the following output:
h%s%s%s%s%s%s%s%s%s%s
he%s%s%s%s%s%s%s%s%s
hel%s%s%s%s%s%s%s%s
hell%s%s%s%s%s%s%s
hello%s%s%s%s%s%s
hello %s%s%s%s%s
hello w%s%s%s%s
hello wo%s%s%s
hello wor%s%s
hello worl%s
hello world
'''

#/usr/bin/env python3
# Initialize an empty string with %s placeholders
phrase = "%s" * 11  # There are 11 characters in "hello world"

# Characters to form "hello world"
characters = ['h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd']

# Initialize an empty string to store the result
result = ""

# Loop through each character and replace the placeholder
for char in characters:
    # Replace the first occurrence of %s with the character
    phrase = phrase.replace("%s", char, 1)
    
    # Append the intermediate phrase to result
    result += phrase + "\n"

    # Store the modified phrase for the next iteration
    phrase = phrase

# Print the final result
print(result)