Blockchain Blog by Dr B P Sharma

pragma solidity >=0.4.22 <0.7.0; abstract contract ERC20Interface {    function totalSupply() virtual public view returns (uint);     function balanceOf(address tokenOwner) virtual public view returns (uint balance);   function allowance (address tokenOwner, address spender) virtual public view returns (uint remaining);     function transfer(address to, uint tokens) virtual public returns (bool success);   function approve(address spender, uint tokens) virtual public returns (bool success);     function transferFrom (address from, address to, uint tokens) virtual public returns (bool success);     event Transfer(address indexed from, address indexed to, uint tokens);     event Approval(address indexed tokenOwner, address indexed spender, uint tokens); } contract EDUCoin is ERC20Interface {     string public name;     string public symbol;     uint8 publi...

pragma solidity >=0.4.22 <0.7.0; contract UniversityCertificate{     //Smart Contract to manage the university degrees     uint256 public year;     string public course;     address public owner;     string public universityId;     string public universityName;             struct Certificate{         string data;         bool isValid;         string enrollmentId;     }         event response(address from, string msg, string methodName);     bytes32[] public allCertificates;     mapping(bytes32=>Certificate) public certificateById;         modifier onlyOwner{         require(msg.sender == owner);         _;     }         //"B.Tech.",2017,"123456","AKTU"     ...