pragma solidity ^0.5.0; contract User { struct UserInfo { string username; bool exist; } mapping(uint256=>UserInfo) public Users; mapping(address=>uint256) public userByAddr; uint256[] usersList; function setUser(string memory _userid,string memory _username) public { uint256 id = uint256(keccak256(abi.encodePacked(_userid))); usersList.push(id); Users[id].exist = true; Users[id].username = _username; userByAddr[tx.origin] = id; } }
0.4.18