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pragma solidity >=0.4.22 <0.6.0;
/**
* Math operations with safety checks
*/
contract SafeMath {
function safeMul(uint256 a, uint256 b) pure internal returns (uint256) {
uint256 c = a * b;
sure(a == 0 || c / a == b);
return c;
}
function safeDiv(uint256 a, uint256 b) pure internal returns (uint256) {
sure(b > 0);
uint256 c = a / b;
sure(a == b * c + a % b);
return c;
}
function safeSub(uint256 a, uint256 b) pure internal returns (uint256) {
sure(b <= a);
return a - b;
}
function safeAdd(uint256 a, uint256 b) pure internal returns (uint256) {
uint256 c = a + b;
sure(c>=a && c>=b);
return c;
}
function sure(bool assertion) pure internal {
require(assertion==true);
}
}
contract LichCoin is SafeMath{
string public name;
string public symbol;
uint8 public decimals;
uint256 public totalSupply;
address payable public owner;
/* This creates an array with all balances */
mapping (address => uint256) public balanceOf;
mapping (address => uint256) public freezeOf;
mapping (address => mapping (address => uint256)) public allowance;
/* This generates a public event on the blockchain that will notify clients */
event Transfer(address indexed from, address indexed to, uint256 value);
/* This notifies clients about the amount burnt */
event Burn(address indexed from, uint256 value);
/* This notifies clients about the amount frozen */
event Freeze(address indexed from, uint256 value);
/* This notifies clients about the amount unfrozen */
event Unfreeze(address indexed from, uint256 value);
/* Initializes contract with initial supply tokens to the creator of the contract */
constructor(
uint256 initialSupply,
string memory tokenName,
uint8 decimalUnits,
string memory tokenSymbol) public {
balanceOf[msg.sender] = initialSupply; // Give the creator all initial tokens
totalSupply = initialSupply; // Update total supply
name = tokenName; // Set the name for display purposes
symbol = tokenSymbol; // Set the symbol for display purposes
decimals = decimalUnits; // Amount of decimals for display purposes
owner = msg.sender;
}
/* Send coins */
function transfer(address _to, uint256 _value) public {
require(_to != 0x0000000000000000000000000000000000000000); // Prevent transfer to 0x0 address. Use burn() instead
require(_value > 0);
require(balanceOf[msg.sender] >= _value); // Check if the sender has enough
require(balanceOf[_to] + _value >= balanceOf[_to]); // Check for overflows
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value); // Subtract from the sender
balanceOf[_to] = SafeMath.safeAdd(balanceOf[_to], _value); // Add the same to the recipient
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
}
/* Allow another contract to spend some tokens in your behalf */
function approve(address _spender, uint256 _value) public returns (bool success) {
if (_value <= 0) revert();
allowance[msg.sender][_spender] = _value;
return true;
}
/* A contract attempts to get the coins */
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
if (_to == 0x0000000000000000000000000000000000000000) revert(); // Prevent transfer to 0x0 address. Use burn() instead
if (_value <= 0) revert();
if (balanceOf[_from] < _value) revert(); // Check if the sender has enough
if (balanceOf[_to] + _value < balanceOf[_to]) revert(); // Check for overflows
if (_value > allowance[_from][msg.sender]) revert(); // Check allowance
balanceOf[_from] = SafeMath.safeSub(balanceOf[_from], _value); // Subtract from the sender
balanceOf[_to] = SafeMath.safeAdd(balanceOf[_to], _value); // Add the same to the recipient
allowance[_from][msg.sender] = SafeMath.safeSub(allowance[_from][msg.sender], _value);
emit Transfer(_from, _to, _value);
return true;
}
function burn(uint256 _value) public returns (bool success) {
if (balanceOf[msg.sender] < _value) revert(); // Check if the sender has enough
if (_value <= 0) revert();
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value); // Subtract from the sender
totalSupply = SafeMath.safeSub(totalSupply,_value); // Updates totalSupply
emit Burn(msg.sender, _value);
return true;
}
function freeze(uint256 _value) public returns (bool success) {
if (balanceOf[msg.sender] < _value) revert(); // Check if the sender has enough
if (_value <= 0) revert();
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value); // Subtract from the sender
freezeOf[msg.sender] = SafeMath.safeAdd(freezeOf[msg.sender], _value); // Updates totalSupply
emit Freeze(msg.sender, _value);
return true;
}
function unfreeze(uint256 _value) public returns (bool success) {
if (freezeOf[msg.sender] < _value) revert(); // Check if the sender has enough
if (_value <= 0) revert();
freezeOf[msg.sender] = SafeMath.safeSub(freezeOf[msg.sender], _value); // Subtract from the sender
balanceOf[msg.sender] = SafeMath.safeAdd(balanceOf[msg.sender], _value);
emit Unfreeze(msg.sender, _value);
return true;
}
// transfer balance to owner
function withdrawEther(uint256 amount) public {
if(msg.sender != owner) revert();
owner.transfer(amount);
}
// can accept ether
function() payable external{
}
}pragma solidity >=0.4.22 <0.6.0;
/**
* Math operations with safety checks
*/
contract SafeMath {
function safeMul(uint256 a, uint256 b) pure internal returns (uint256) {
uint256 c = a * b;
sure(a == 0 || c / a == b);
return c;
}
function safeDiv(uint256 a, uint256 b) pure internal returns (uint256) {
sure(b > 0);
uint256 c = a / b;
sure(a == b * c + a % b);
return c;
}
function safeSub(uint256 a, uint256 b) pure internal returns (uint256) {
sure(b <= a);
return a - b;
}
function safeAdd(uint256 a, uint256 b) pure internal returns (uint256) {
uint256 c = a + b;
sure(c>=a && c>=b);
return c;
}
function sure(bool assertion) pure internal {
require(assertion==true);
}
}
contract TestCoin is SafeMath{
string public name;
string public symbol;
uint8 public decimals;
uint256 public totalSupply;
address payable public owner;
/* This creates an array with all balances */
mapping (address => uint256) public balanceOf;
mapping (address => uint256) public freezeOf;
mapping (address => mapping (address => uint256)) public allowance;
/* This generates a public event on the blockchain that will notify clients */
event Transfer(address indexed from, address indexed to, uint256 value);
/* This notifies clients about the amount burnt */
event Burn(address indexed from, uint256 value);
/* This notifies clients about the amount frozen */
event Freeze(address indexed from, uint256 value);
/* This notifies clients about the amount unfrozen */
event Unfreeze(address indexed from, uint256 value);
/* Initializes contract with initial supply tokens to the creator of the contract */
constructor(
uint256 initialSupply,
string memory tokenName,
uint8 decimalUnits,
string memory tokenSymbol) public {
balanceOf[msg.sender] = initialSupply; // Give the creator all initial tokens
totalSupply = initialSupply; // Update total supply
name = tokenName; // Set the name for display purposes
symbol = tokenSymbol; // Set the symbol for display purposes
decimals = decimalUnits; // Amount of decimals for display purposes
owner = msg.sender;
}
/* Send coins */
function transfer(address _to, uint256 _value) public {
require(_to != 0x0000000000000000000000000000000000000000); // Prevent transfer to 0x0 address. Use burn() instead
require(_value > 0);
require(balanceOf[msg.sender] >= _value); // Check if the sender has enough
require(balanceOf[_to] + _value >= balanceOf[_to]); // Check for overflows
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value); // Subtract from the sender
balanceOf[_to] = SafeMath.safeAdd(balanceOf[_to], _value); // Add the same to the recipient
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
}
/* Allow another contract to spend some tokens in your behalf */
function approve(address _spender, uint256 _value) public returns (bool success) {
if (_value <= 0) revert();
allowance[msg.sender][_spender] = _value;
return true;
}
/* A contract attempts to get the coins */
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
if (_to == 0x0000000000000000000000000000000000000000) revert(); // Prevent transfer to 0x0 address. Use burn() instead
if (_value <= 0) revert();
if (balanceOf[_from] < _value) revert(); // Check if the sender has enough
if (balanceOf[_to] + _value < balanceOf[_to]) revert(); // Check for overflows
if (_value > allowance[_from][msg.sender]) revert(); // Check allowance
balanceOf[_from] = SafeMath.safeSub(balanceOf[_from], _value); // Subtract from the sender
balanceOf[_to] = SafeMath.safeAdd(balanceOf[_to], _value); // Add the same to the recipient
allowance[_from][msg.sender] = SafeMath.safeSub(allowance[_from][msg.sender], _value);
emit Transfer(_from, _to, _value);
return true;
}
function burn(uint256 _value) public returns (bool success) {
if (balanceOf[msg.sender] < _value) revert(); // Check if the sender has enough
if (_value <= 0) revert();
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value); // Subtract from the sender
totalSupply = SafeMath.safeSub(totalSupply,_value); // Updates totalSupply
emit Burn(msg.sender, _value);
return true;
}
function freeze(uint256 _value) public returns (bool success) {
if (balanceOf[msg.sender] < _value) revert(); // Check if the sender has enough
if (_value <= 0) revert();
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value); // Subtract from the sender
freezeOf[msg.sender] = SafeMath.safeAdd(freezeOf[msg.sender], _value); // Updates totalSupply
emit Freeze(msg.sender, _value);
return true;
}
function unfreeze(uint256 _value) public returns (bool success) {
if (freezeOf[msg.sender] < _value) revert(); // Check if the sender has enough
if (_value <= 0) revert();
freezeOf[msg.sender] = SafeMath.safeSub(freezeOf[msg.sender], _value); // Subtract from the sender
balanceOf[msg.sender] = SafeMath.safeAdd(balanceOf[msg.sender], _value);
emit Unfreeze(msg.sender, _value);
return true;
}
// transfer balance to owner
function withdrawEther(uint256 amount) public {
if(msg.sender != owner) revert();
owner.transfer(amount);
}
// can accept ether
function() payable external{
}
}