How to Use Counter in Python

from collections import Counter

# Count list items
numbers = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4]
counter = Counter(numbers)
print(f"Counter: {counter}")

# Most common
print(f"\nMost common: {counter.most_common(3)}")

# Count string
text = "hello world"
char_count = Counter(text)
print(f"\nChar count: {char_count}")
print(f"Most common chars: {char_count.most_common(5)}")

# Update counter
counter.update([5, 5, 5])
print(f"\nAfter update: {counter}")

# Access counts
print(f"\nCount of 4: {counter[4]}")
print(f"Count of 99: {counter[99]}")  # Returns 0

# Counter operations
c1 = Counter("abracadabra")
c2 = Counter("alacazam")
print(f"\nAddition: {c1 + c2}")
print(f"Subtraction: {c1 - c2}")
print(f"Intersection: {c1 & c2}")
print(f"Union: {c1 | c2}")

# Practical example
words = ["apple", "banana", "apple", "cherry", "banana", "apple"]
word_freq = Counter(words)
print(f"\nWord frequencies: {word_freq}")
print(f"Top 2: {word_freq.most_common(2)}")