Lambda & Comprehensions

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add = lambda x, y: x + y
squared = list(map(lambda x: x**2, [1,2,3]))
evens = list(filter(lambda x: x%2==0, range(10)))

d = {x: x**2 for x in range(6)}
gen = (x**2 for x in range(1000000))

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# Lambdas
square = lambda x: x * x
print("Square:", square(5))

add = lambda a, b: a + b
print("Add:", add(3, 4))

# map / filter / sorted
nums = [3, 1, 4, 1, 5]
doubled = list(map(lambda n: n * 2, nums))
evens = list(filter(lambda n: n % 2 == 0, nums))
print("Doubled:", doubled)
print("Evens:", evens)

# List comprehension
squares = [x * 2 for x in range(1, 6)]
even_squares = [x * x for x in range(1, 21) if x % 2 == 0]
print("Squares:", squares)
print("Even squares:", even_squares)

# Dict comprehension
lengths = {word: len(word) for word in ["cat", "elephant", "dog"]}
print("Lengths:", lengths)