Combine map + filter + reduce in a single program Dry Run in PYTHON

Combine map + filter + reduce in a single program is an interactive PYTHON dry run visualizer from the Special programs section. Study the source code, then use the execution controls to follow each step, variable update, highlighted line, and console output.

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Combine map + filter + reduce in a single program Program Code

from functools import reduce

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

# Pipeline: filter even → square → sum of first 5
result = reduce(
    lambda acc, x: acc + x,
    list(map(lambda x: x ** 2, filter(lambda x: x % 2 == 0, numbers)))[:5]
)

print(f"Sum of squares of first 5 even numbers: {result}")

# One-liner version
result2 = reduce(lambda a, b: a + b, list(map(lambda x: x ** 2, filter(lambda x: x % 2 == 0, numbers)))[:5])
print(f"Same result: {result2}")

# Generic pipeline function
def pipeline(data, *functions):
    for func in functions:
        data = func(data)
    return data

result3 = pipeline(
    numbers,
    lambda x: filter(lambda n: n % 2 == 0, x),  # Filter even
    lambda x: map(lambda n: n ** 2, x),          # Square them
    lambda x: list(x)[:5],                       # Take first 5
    lambda x: reduce(lambda a,b: a+b, x)         # Sum them
)
print(f"Using pipeline function: {result3}")

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