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keccak256Test.sol

pragma solidity >=0.4.22 <0.7.0;

/** 
 * updated original from https://ethereum.github.io/browser-solidity/#gist=f50128d63b5188490fa2&optimize=false&version=soljson-v0.7.1+commit.f4a555be.js
 * more info: https://github.com/vkli/Digital-Week-Online-Ethereum-Online2020
 */

contract keccak256Test
{
    function getkeccak256Hash() public view returns (bytes32)
    {
        return keccak256("testing");
    }
    
}

// Ethereum uses KECCAK-256. It should be noted that it does not follow 
// the FIPS-202 based standard of Keccak, which was finalized in August 2015.

// Hashing the string "testing":
// Ethereum SHA3 function in Solidity = 5f16f4c7f149ac4f9510d9cf8cf384038ad348b3bcdc01915f95de12df9d1b02
// Keccak-256 (Original Padding) = 5f16f4c7f149ac4f9510d9cf8cf384038ad348b3bcdc01915f95de12df9d1b02
// SHA3-256 (NIST Standard) = 7f5979fb78f082e8b1c676635db8795c4ac6faba03525fb708cb5fd68fd40c5e

// More info:
// https://github.com/ethereum/EIPs/issues/59
// http://ethereum.stackexchange.com/questions/550/which-cryptographic-hash-function-does-ethereum-use