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  • Jun 05 2016 10:31
    @alexvandesande banned @adamskee
  • Mar 16 2016 01:12
    @alexvandesande banned @scbosse
Raheel Aslam
@raheelll
Hi
Please Can ethereum Devs guide what i need for creating the ERC20 token and get reward on base of taken ?
?
@zhang3333333 ?
amazonmonkey1974
@amazonmonkey1974
Hi, I am 100% new to smart contracts and am looking for a combined token and crowdsale contract that is secure. I copied some code from a site that is basically a tutorial but when I put it through Securify it gave me all kinds of errors. Is there anyplace I can find what I am looking for?
ThisIsCodeXpert
@ThisIsCodeXpert
@amazonmonkey1974 Take a look at this channel. It has many nice tutorials for beginner as well as intermediate learners : https://www.youtube.com/channel/UCb3Rrg2t4PZ59Sna497DUZA?sub_confirmation=1
Nicole Zhu
@nczhu

Hey everyone,
Here’s a technical walkthrough series for Ethernaut’s smart contract hacking puzzles. It’s been a good learning resource to dive deeper into the vulnerabilities of Solidity, i.e. a Turing complete language on the blockchain.

Thought I’d document my learning journey for public benefit here: https://hackernoon.com/ethernaut-lvl-1-walkthrough-how-to-abuse-the-fallback-function-118057b68b56

Deepakguru1990
@Deepakguru1990
Hi All. I am unable to find the accounts reflecting in remix(web3 provider), I am using ethjsonrpc from aws ethereum blockchain templates
Singh
@Nitishkumar3211
where Public key and private key generates . On blockchain or local wallet ?
Deepakguru1990
@Deepakguru1990
Hi All. I am unable to find the accounts reflecting in remix(web3 provider), I am using ethjsonrpc from aws ethereum blockchain templates
Deepakguru1990
@Deepakguru1990
Hi all
want to know about designing smart contracts
for a supply chain use case
ThisIsCodeXpert
@ThisIsCodeXpert
@Deepakguru1990 You can checkout this channel, it has many great tutorials : https://www.youtube.com/channel/UCb3Rrg2t4PZ59Sna497DUZA?sub_confirmation=1
Deepakguru1990
@Deepakguru1990
I have 4 actors and each perform similar functions like create asset, transfer asset, receive, reject
will it be a good design to have 4 contracts each for 1 actor
or i can have them as 2 contracts -> first contract between first actor and second actor(asset shape is different), second contract between second actor and the rest of actors in the chain(asset shape is different)
Deepakguru1990
@Deepakguru1990
Who performs mining in the private blockchain created using cloud providers?
ThisIsCodeXpert
@ThisIsCodeXpert
@Deepakguru1990 Please ask question on any one of the channel. Do not spam everywhere
Deepakguru1990
@Deepakguru1990
Sure. Couldn't find a suitable group, hence asked everywhere. Intention was to get the answer not to spam!!
Singh
@Nitishkumar3211
How blockchain maintain addresses collision. ? anyone knows ?
ABSoftech
@ABSoftech
I have made coding on cryptocurrency, in java. how can i enlist that in blockchain
Nicole Zhu
@nczhu

@sierra1bravo Hey Sierra, in general, you don't want to use "transfer" to move tokens around. Try using the approve+transferfrom combo, see why transfer opens you to security issues here: https://medium.com/coinmonks/ethernaut-lvl-15-naught-coin-walkthrough-how-to-abuse-erc20-tokens-and-bad-icos-6668b856a176. Transfer() was how a lot of ICOs got tokens permanently locked.

Try pasting your code into RemixIDE to get started with the least setup time: http://remix.ethereum.org/

Manish Ranjan
@bit-warrior
Hello guys please try http://blockaction.io/
Bringing web3 to browser
Sierra Bravo
@sierra1bravo
Thanks @nczhu. Will try as suggested.
dhitaishin
@dhitaishin
Hello
I am confused when i transfer ERC20 tokens from one account to other the fee is deducted from ETH account i want to the gas fee is apply direct from token account balance not from ETH balance.
blockchaintrainer
@blockchaintrainer
Hi Guys, I am a blockchain developer working on Bitcoin and other blockchains previously, Now I am planning to launch an huge ICO of my own publicly, I see there is lot of help available including on the website ethereum.org. I am looking to find the best and most efficient way to do this? Can some one please help me out?
Frankinvestor
@Frankinvestor
hello sir
Generating account ethreum wallet
Paul Nguyen
@Paulnguyenun
Hello Sir
Nice to meet you
Singh
@Nitishkumar3211
@dhitaishin Use Feeless smart contract
ardiankrasniqi
@ardiankrasniqi
can anyone help me with smth?
Paul Nguyen
@Paulnguyenun
Hello
baophucct
@baophucct

pragma solidity ^0.4.20;

contract MyToken {
/ This creates an array with all balances /
mapping (address => uint256) public balanceOf;

/* Initializes contract with initial supply tokens to the creator of the contract */
function MyToken(
    uint256 initialSupply
    ) public {
    balanceOf[msg.sender] = initialSupply;              // Give the creator all initial tokens
}

/* Send coins */
function transfer(address _to, uint256 _value) public returns (bool success) {
    require(balanceOf[msg.sender] >= _value);           // Check if the sender has enough
    require(balanceOf[_to] + _value >= balanceOf[_to]); // Check for overflows
    balanceOf[msg.sender] -= _value;                    // Subtract from the sender
    balanceOf[_to] += _value;                           // Add the same to the recipient
    return true;
}

}

Harry Vn
@Harry30000
Hello
i try to deloy contract but can't . nothing happen when clik deloy with example code
anyone can help ?
Sierra Bravo
@sierra1bravo
@Harry30000 Both the code samples should work. How did you try to deploy the code?
baophucct
@baophucct
contract MyToken {
    /* This creates an array with all balances */
    mapping (address => uint256) public balanceOf;
}
function MyToken() public {
balanceOf[msg.sender] = 21000000;
}
function MyToken(uint256 initialSupply) public {
    balanceOf[msg.sender] = initialSupply;
}
Paul Nguyen
@Paulnguyenun
Hello
CryptoEmpire
@cryptoempire
Are there any dapp tutorials that use react as a front-end? Any resources are helpful
Coinmonks has lot of tutorials,and everything is free...you can checkout learn build and share to others