// SPDX-License-Identifier: MIT pragma solidity >=0.4.0 <0.7.0; contract SimpleStorage { uint storedData; function set(uint x) public { storedData = x; } function get() public view returns (uint) { return storedData; } } //—------------------------------------------ pragma solidity >=0.8.9 <0.8.0; contract NewWorld { function New() pure public returns(string memory) { return NewWorld; } } contract NewWorld { string public data; function set(string memory_data) public { } function get () view public returns (string memory) { return data ; } } //==================================== contract NewWorld { uint [] public ids; function add (uint id) public { ids.push(id); } function get (uint position) view public returns (uint) { return ids[position]; } function getAll () view public returns (uint[] memory){ return ids; } function length () view public returns (uint) { return ids.length; } } contract crud { struct User { uint id; string name; } User [] public users; unint public nextId; function create (string memory name) public { users.push(Users(nextId, name)); nextId++; } function read (uint Id) view public returns (uint, string memory) { uint i = find (id); if (users[i].id == id) { return (users[id].id , users[i].name); } } function update (uint id, string memory name) public { uint i = find (id); users[i].name = name; } function destroy (uint id) public { uint i = find (id); delete users [i]; } function find (uint id) view internal returns (uint) { for (uint i=0 ; i < users.length; i ++){ if (users[i].id == id) { return i; } } revert("users doesn’t exist!"); } }
0.4.18