openzeppelin-contracts/contracts/examples/SimpleToken.sol

pragma solidity ^0.4.24;

import "../token/ERC20/ERC20.sol";
import "../token/ERC20/ERC20Detailed.sol";

/**
 * @title SimpleToken
 * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
 * Note they can later distribute these tokens as they wish using `transfer` and other
 * `ERC20` functions.
 */
contract SimpleToken is ERC20, ERC20Detailed {
    uint256 public constant INITIAL_SUPPLY = 10000 * (10 ** uint256(decimals()));

    /**
     * @dev Constructor that gives msg.sender all of existing tokens.
     */
    constructor () public ERC20Detailed("SimpleToken", "SIM", 18) {
        _mint(msg.sender, INITIAL_SUPPLY);
    }
}