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PwrDem

Modular Exponentiation Demonstration

Demonstrates how to compute ak(modm)a^k \pmod{m} using different algorithms

Understanding Modular Exponentiation

This algorithm calculates ak(modm)a^k \pmod{m} using various methods. The binary methods express the exponent kk in binary form and process the bits either left-to-right or right-to-left. The square-and-multiply method repeatedly squares and conditionally multiplies based on the binary representation of the exponent.
  1. 1Convert exponent kk into binary form (for binary methods).
  2. 2Initialize the result appropriately for the chosen method.
  3. 3Process the binary representation of kk:
  4. 4- Square-and-multiply: use repeated squaring with conditional multiplication
  5. 5- Right-to-left: scan from least significant to most significant bit
  6. 6- Left-to-right: scan from most significant to least significant bit
  7. 7Apply modular arithmetic at each step to keep numbers manageable.
  8. 8The final result is akmodma^k \bmod m.