Add zkCTF wp

.gitignore

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-site
+site
+.DS_Store

docs/crypto/2+2=5/two_plus_two.md

@@ -3,6 +3,11 @@ title: Jolt zkVM - 2+2=5
 description: 2024 | MOCA Italian Hacker Camp | Crypto
 ---
 
+- [1. Background](#1-background)
+- [2. Puzzle Description](#2-puzzle-description)
+- [3. Alynasis](#3-alynasis)
+- [4. EXP](#4-exp)
+
 ## 1. Background
 
 [Jolt](https://jolt.a16zcrypto.com/intro.html) 是由 A16Z 的密码学家们提出的一个针对 Risc-V ISA （未来将支持更多ISA）的 zkVM 框架，它底层使用了 sumcheck-based SNARK，这个 SNARK 充分利用多变量多项式及其多项式承诺的优势。Jolt zkVM 据说拥有非常出色的性能表现并且还存在优化空间。

docs/crypto/zkCTF/day1/Division Quiz/.gitignore

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+/target
+Cargo.lock
+param
+proof
+vk

docs/crypto/zkCTF/day1/Division Quiz/Cargo.toml

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+[package]
+name = "cft"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+backtrace = { version = "0.3", optional = true }
+ff = "0.13"
+halo2_proofs = { git = "https://github.com/privacy-scaling-explorations/halo2.git", default-features = true }
+clap = "3.0"
+halo2curves = { version = "0.6.0", default-features = false }
+rand = "0.8"

docs/crypto/zkCTF/day1/Division Quiz/description.md

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+# ZK  CFT - Halo2 - Int Division
+
+## Overview
+1. This is a quiz about Halo2 usage. The standard answer would not be given to participants
+2. Instead, a file would be given, with all necessary structs and missing logics. Participants are required to fill in the blanks, compile the program and run tests
+3. Multiple test cases would be given, the prover program shall be tested against them
+
+## Problem description
+While doing proof we always face some basic arithematics, such as int division. It is a very intuitive operation on normal programming language, but one might find it a bit harder when doing it in crypto world -- for we always use [Finte Field](https://en.wikipedia.org/wiki/Finite_field). For each non-zero element, it has inverse, so that a normal int division is not obeying ordinary division just like Python. For example, in Fp where p = 11, 10 div 3 = 7 mod 11 -- for inverse of 3 is 4, 11 div 3 = 10 times 4 = 7 mod 11. While we expect an 'ordinary' int division: 10 // 3 = 3. Now you are required to simulate an int division in Halo2. We limit the size as U8. So you are actually implementing an U8 division in a finite file Fr, which is the scalar field of ecliptic curve group BN256.
+
+## Comand
+cargo run  
+
+## Example
+Input 10 3 3
+Explain: Proof generates and verifier passes it. It is an U8 division
+
+## Solve
+Sumbit quiz.rs to solve the puzzle.
+

docs/crypto/zkCTF/day1/Division Quiz/src/lib.rs

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+pub mod quiz;