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Coding workflows · Fast-doubling Fibonacci
03
A concrete starting point
Compute Fibonacci numbers by fast doubling for integer indices from zero through 10000. Check the first two values, a known larger term and the upper bound, rejecting fractional, negative or Boolean indices.
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Fast-doubling Fibonacci
A concrete starting point
def fibonacci(index):
if type(index) is not int or not 0 <= index <= 10000:
raise ValueError("index.range")
a, b = 0, 1
for bit in bin(index)[2:]:
c = a * (2 * b - a)
d = a * a + b * b
a, b = (c, d) if bit == "0" else (d, c + d)
return aThe example is a starting point for a real project, not a claim that generated code is already tested. Adjust paths, dependencies and expected behavior to match your application.