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@dappadda

dappadda/ERC20.sol Secret

Created Oct 26, 2020
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pragma solidity ^0.7.0;
contract SafeMath {
function safeAdd(uint a, uint b) public pure returns (uint c) {
c = a + b;
require(c >= a);
}
function safeSub(uint a, uint b) public pure returns (uint c) {
require(b <= a);
c = a - b;
}
function safeMul(uint a, uint b) public pure returns (uint c) {
c = a * b;
require(a == 0 || c / a == b);
}
function safeDiv(uint a, uint b) public pure returns (uint c) {
require(b > 0);
c = a / b;
}
}
interface ERC20Interface {
function totalSupply() external returns (uint);
function balanceOf(address tokenOwner) external returns (uint balance);
function allowance(address tokenOwner, address spender) external returns (uint remaining);
function transfer(address to, uint tokens) external returns (bool success);
function approve(address spender, uint tokens) external returns (bool success);
function transferFrom(address from, address to, uint tokens) external returns (bool success);
event Transfer(address indexed from, address indexed to, uint tokens);
event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
}
contract Ownership {
address public owner;
address public newOwner;
event OwnershipTransferred(address indexed _from, address indexed _to);
constructor() {
owner = msg.sender;
}
modifier onlyOwner {
require(msg.sender == owner);
_;
}
function transferOwnership(address _newOwner) public onlyOwner {
newOwner = _newOwner;
}
function acceptOwnership() public {
require(msg.sender == newOwner);
emit OwnershipTransferred(owner, newOwner);
owner = newOwner;
newOwner = address(0);
}
}
contract MyERC20Token is ERC20Interface, Ownership, SafeMath {
string public symbol;
string public name;
uint8 public decimals;
uint public _totalSupply;
mapping(address => uint) balances;
mapping(address => mapping(address => uint)) allowed;
constructor() {
symbol = "SKA";
name = "SKA's Token";
decimals = 18;
_totalSupply = 10000000000000000000000000;
}
function totalSupply() public override view returns (uint) {
return _totalSupply;
}
function balanceOf(address tokenOwner) public view override returns (uint balance) {
return balances[tokenOwner];
}
function transfer(address to, uint tokens) public override returns (bool success) {
require(balances[msg.sender] >= tokens);
balances[msg.sender] = safeSub(balances[msg.sender], tokens);
balances[to] = safeAdd(balances[to], tokens);
emit Transfer(msg.sender, to, tokens);
return true;
}
function approve(address spender, uint tokens) public override returns (bool success) {
allowed[msg.sender][spender] = tokens;
emit Approval(msg.sender, spender, tokens);
return true;
}
function transferFrom(address from, address to, uint tokens) public override returns (bool success) {
require(allowed[from][to] >= tokens);
balances[from] = safeSub(balances[from], tokens);
allowed[from][msg.sender] = safeSub(allowed[from][msg.sender], tokens);
balances[to] = safeAdd(balances[to], tokens);
emit Transfer(from, to, tokens);
return true;
}
function allowance(address tokenOwner, address spender) public view override returns (uint remaining) {
return allowed[tokenOwner][spender];
}
fallback () external payable {
revert();
}
}
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