openzeppelin-contracts/contracts/token/BasicToken.sol

pragma solidity ^0.4.4;

import './ERC20Basic.sol';
import '../SafeMath.sol';

/**
 * Basic token
 * Basic version of StandardToken, with no allowances
 */
contract BasicToken is ERC20Basic, SafeMath {

  mapping(address => uint) balances;

  function transfer(address _to, uint _value) returns (bool success) {
    if (balances[msg.sender] < _value) {
      throw;
    } 
    balances[msg.sender] = safeSub(balances[msg.sender], _value);
    balances[_to] = safeAdd(balances[_to], _value);
    Transfer(msg.sender, _to, _value);
    return true;
  }

  function balanceOf(address _owner) constant returns (uint balance) {
    return balances[_owner];
  }
  
}