import math as math
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def fib(n):
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if n == 0 or n == 1:
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return n
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return fib(n-1) + fib(n-2)
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def fibHelper(n, a, b):
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if n == 0:
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return a
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elif n == 1:
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return b
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return fibHelper(n-1, b, a+b)
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def fibIterative(n):
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return fibHelper(n, 0, 1)
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def multiply(a,b):
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product = [0,0,0]
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product[0] = a[0]*b[0] + a[1]*b[1]
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product[1] = a[0]*b[1] + a[1]*b[2]
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product[2] = a[1]*b[1] + a[2]*b[2]
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return product
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def power(l, k):
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if k == 1:
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return l
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temp = power(l, k//2)
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if k%2 == 0:
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return multiply(temp, temp)
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else:
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return multiply(l, multiply(temp, temp))
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def fibPower(n):
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l = [1,1,0]
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return power(l, n)[1]
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def fibClosedFormula(n):
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p = ((1+ math.sqrt(5))/2)**n
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v = ((1-math.sqrt(5))/2)**n
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return (p-v)/math.sqrt(5)
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"""
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Makes sure that other programs don't execute the main
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"""
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if __name__ == '__main__':
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try:
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print(closedFormula(6))
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except KeyboardInterrupt:
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exit()
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