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Book of PQC

Appendix D: Solutions

This appendix collects a worked solution for every compute and derivation exercise, and an editorial note on what a strong answer addresses for every open-ended one. One page per chapter, ordered by chapter number.

Two kinds of entries appear:

  1. Solutions for compute and derivation exercises (run the toy code, do the arithmetic, walk the proof). The entry shows the worked answer with code, math, and any derivation steps.
  2. Editorial notes for open-ended exercises (defend a position, design a system, write a paragraph of analysis with no single canonical answer). The entry frames what a strong response addresses (sources to cite, distinctions to make, traps to avoid) without imposing one right answer.

The routines worked here also ship as code. Each chapter has a reference package under solutions/ in the companion repository, the same package with its taught functions stubbed under exercises/, and a pytest suite under tests/ that proves either tree. Appendix C: Environment setup walks the clone, the environment, and how to run them.

Every chapter that has an Exercises section has a corresponding page here. Notation follows Appendix B: Notation. Terms used in solutions but not redefined here have their definitions in Appendix A: Glossary.

Part I: Foundations

Section titled “Part I: Foundations”

Part II: Lattice-based cryptography

Section titled “Part II: Lattice-based cryptography”

Part III: Hash-based signatures

Section titled “Part III: Hash-based signatures”

Part IV: Code-based and isogeny-based cryptography

Section titled “Part IV: Code-based and isogeny-based cryptography”

Part V: Migration and deployment

Section titled “Part V: Migration and deployment”

Part VI: Post-quantum zero-knowledge

Section titled “Part VI: Post-quantum zero-knowledge”

Part VII: Post-quantum blockchain

Section titled “Part VII: Post-quantum blockchain”