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Re: C Question for P. Olcott

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Moreover, Peter, do you understand why this code works:

#!/usr/bin/env python3

# Combinateur de point fixe (Y adapté à Python, appel par valeur)
Y = lambda f: (lambda x: f(lambda *args: x(x)(*args)))(
                  lambda x: f(lambda *args: x(x)(*args))
              )

# Exemple 1 : factorielle sans récursion directe
fact = Y(
    lambda rec: lambda n: 1 if n == 0 else n * rec(n - 1)
)

# Exemple 2 : Fibonacci sans récursion directe
fib = Y(
    lambda rec: lambda n: n if n < 2 else rec(n - 1) + rec(n - 2)
)

if __name__ == "__main__":
    for n in range(6):
        print(f"fact({n}) =", fact(n))

    for n in range(8):
        print(f"fib({n})  =", fib(n))

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C Question for P. Olcott Python <python@cccp.invalid> - 2025-11-26 03:02 +0000
  Re: C Question for P. Olcott Python <python@cccp.invalid> - 2025-11-26 03:50 +0000

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