Challenges
Test your understanding of blockchain and cryptography concepts
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1. Break the Hash
Find a string whose SHA-256 hash starts with "0000". Time yourself. Then try "00000". Feel the exponential difficulty increase.
2. Double Spend Attack
Using the Fork Explorer, successfully execute a double-spend: send coins to Alice on one fork, then make the other fork (where you kept your coins) win. Requires >50% hash power.
3. Merkle Proof Verification
Given a Merkle root and a transaction, construct the minimum proof needed to verify the transaction is in the tree. How many hashes do you need for a tree with 1024 leaves?
4. Byzantine Generals
In the Consensus Simulator, set exactly 1/3 of nodes to Byzantine. Observe that PBFT still reaches consensus. Then add one more Byzantine node. Watch it break.
5. Impermanent Loss
In the AMM Simulator, provide liquidity when ETH = $2000. Wait until ETH = $4000. Calculate your impermanent loss vs just holding. When is it actually worth providing liquidity?
6. Zero-Knowledge Convince
Play the Prover in the ZKP demo. Convince the Verifier you know the secret in exactly 10 rounds. What's the probability the Verifier is fooled if you don't actually know it?
7. Design a Tokenomics
Create a token with deflationary supply (burns on transfer) using the Token Creator. Set parameters so the token reaches 0 supply in exactly 1000 transfers of 100 tokens each. What burn rate do you need?