// File: contracts/Library/IERC20.sol
pragma solidity ^0.5.11;
interface IERC20 {
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
function transfer(address to, uint256 value) external returns (bool);
function transferFrom(address from, address to, uint256 value)
external
returns (bool);
function approve(address spender, uint256 value) external returns (bool);
function balanceOf(address target) external view returns (uint256);
function allowance(address target, address spender)
external
view
returns (uint256);
}
// File: contracts/Library/SafeMath.sol
pragma solidity ^0.5.11;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*
* _Available since v2.4.0._
*/
function sub(uint256 a, uint256 b, string memory errorMessage)
internal
pure
returns (uint256)
{
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*
* _Available since v2.4.0._
*/
function div(uint256 a, uint256 b, string memory errorMessage)
internal
pure
returns (uint256)
{
// Solidity only automatically asserts when dividing by 0
require(b > 0, errorMessage);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts with custom message when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*
* _Available since v2.4.0._
*/
function mod(uint256 a, uint256 b, string memory errorMessage)
internal
pure
returns (uint256)
{
require(b != 0, errorMessage);
return a % b;
}
}
// File: contracts/WithCoffeeToken.sol
pragma solidity ^0.5.11;
contract WithCoffeeToken is IERC20 {
using SafeMath for uint256;
mapping(address => uint256) private balances;
mapping(address => mapping(address => uint256)) allowances;
string public constant name = "With ☕️";
string public constant symbol = "With ☕️";
uint8 public constant decimals = 18;
uint256 public constant totalSupply = 165e18;
constructor() public {
balances[msg.sender] = totalSupply;
}
function transfer(address to, uint256 value) external returns (bool) {
balances[msg.sender] = balances[msg.sender].sub(
value,
"With ☕️/Not-Enough-Balance"
);
balances[to] = balances[to].add(value);
emit Transfer(msg.sender, to, value);
return true;
}
function transferFrom(address from, address to, uint256 value)
external
returns (bool)
{
allowances[from][msg.sender] = allowances[from][msg.sender].sub(
value,
"With ☕️/Not-Enough-Allowance"
);
balances[from] = balances[from].sub(
value,
"With ☕️/Not-Enough-Balance"
);
balances[to] = balances[to].add(value);
emit Transfer(from, to, value);
return true;
}
function approve(address spender, uint256 value) external returns (bool) {
allowances[msg.sender][spender] = value;
emit Approval(msg.sender, spender, value);
return true;
}
function balanceOf(address target) external view returns (uint256) {
return balances[target];
}
function allowance(address target, address spender)
external
view
returns (uint256)
{
return allowances[target][spender];
}
}
{
"compilationTarget": {
"WithCoffeeToken.sol": "WithCoffeeToken"
},
"evmVersion": "petersburg",
"libraries": {},
"optimizer": {
"enabled": true,
"runs": 999
},
"remappings": []
}
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