Binary Exponentiation Formula:
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Binary exponentiation (also known as exponentiation by squaring) is an efficient algorithm for computing large exponents modulo a number. It reduces the time complexity from O(n) to O(log n), making it essential for cryptographic applications and large number computations.
The calculator uses the binary exponentiation algorithm:
Algorithm Steps:
Details: Modular exponentiation is fundamental in public-key cryptography (RSA, Diffie-Hellman), primality testing, and various number theory applications. Its efficiency makes secure digital communications possible.
Tips: Enter integer values for base, exponent, and modulus. The modulus must be a positive integer greater than 0. The calculator efficiently computes even very large exponents.
Q1: Why use binary exponentiation instead of direct computation?
A: Direct computation becomes infeasible for large exponents due to enormous intermediate values. Binary exponentiation handles large numbers efficiently.
Q2: What is the time complexity of this algorithm?
A: O(log n), where n is the exponent, making it exponentially faster than naive approaches.
Q3: Can this handle negative exponents?
A: This implementation handles non-negative exponents only. For negative exponents, modular inverses would be needed.
Q4: What are the practical applications?
A: Cryptography, computer algebra systems, computational number theory, and anywhere large modular exponentiations are required.
Q5: Are there limitations to this algorithm?
A: The algorithm assumes integer inputs and may have precision limitations with extremely large numbers in some implementations, though PHP handles big integers well.