# Dot (.): Matches any character except a newline.
pattern = r"."
match = re.findall(pattern, "Hello\nWorld")
print(match)

# Caret (^): Matches the start of a string
pattern = r"^Hello"
match = re.findall(pattern, "Hello World")
print(match)

# Dollar ($): Matches the end of a string
pattern = r"World$"
match = re.findall(pattern, "Hello World")
print(match)

# Asterisk (*): Matches 0 or more repetitions of the preceding
pattern = r"a*"
match = re.findall(pattern, "aaaab")
print(match)

# Plus (+): Matches 1 or more repetitions of the preceding character
pattern = r"a+"
match = re.findall(pattern, "aaaab")
print(match)

# Question Mark (?): Matches 0 or 1 repetition of the preceding
pattern = r"ab?"
match = re.findall(pattern, "a ab abb")
print(match)

# Braces ({}): Matches a specified number of repetitions of the preceding character
pattern = r"a{2,3}"
match = re.findall(pattern, "a aa aaa aaaa")
print(match)

# Square Brackets ([]): Matches any one of the characters inside the brackets
pattern = r"[aeiou]"
match = re.findall(pattern, "Hello World")
print(match)

# Backslash (\): Escapes special characters or denotes special sequences
pattern = r"\d"  
match = re.findall(pattern, "There are 2 apples")
print(match)

import re

text = "The price is $123.45 on 2024-10-07."
pattern = r"\$\d+\.\d{2}"
matches = re.findall(pattern, text)
print(matches)
pattern = r"\d{4}-\d{2}-\d{2}"
matches = re.findall(pattern, text)
print(matches)