TheAlgorithms-Python/maths/binary_exponentiation.py

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"""Binary Exponentiation."""
# Author : Junth Basnet
# Time Complexity : O(logn)
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def binary_exponentiation(a, n):
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if (n == 0):
return 1
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elif (n % 2 == 1):
return binary_exponentiation(a, n - 1) * a
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else:
b = binary_exponentiation(a, n / 2)
return b * b
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try:
BASE = int(input('Enter Base : '))
POWER = int(input("Enter Power : "))
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except ValueError:
print("Invalid literal for integer")
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RESULT = binary_exponentiation(BASE, POWER)
print("{}^({}) : {}".format(BASE, POWER, RESULT))