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Basic ERC20 implementation
pragma solidity ^0.4.19;
contract ERC20Basic {
string public constant name = "ERC20Basic";
string public constant symbol = "BSC";
uint8 public constant decimals = 18;
event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
event Transfer(address indexed from, address indexed to, uint tokens);
mapping(address => uint256) balances;
mapping(address => mapping (address => uint256)) allowed;
uint256 totalSupply_;
using SafeMath for uint256;
constructor(uint256 total) public {
totalSupply_ = total;
balances[msg.sender] = totalSupply_;
function totalSupply() public view returns (uint256) {
return totalSupply_;
function balanceOf(address tokenOwner) public view returns (uint) {
return balances[tokenOwner];
function transfer(address receiver, uint numTokens) public returns (bool) {
require(numTokens <= balances[msg.sender]);
balances[msg.sender] = balances[msg.sender].sub(numTokens);
balances[receiver] = balances[receiver].add(numTokens);
emit Transfer(msg.sender, receiver, numTokens);
return true;
function approve(address delegate, uint numTokens) public returns (bool) {
allowed[msg.sender][delegate] = numTokens;
Approval(msg.sender, delegate, numTokens);
return true;
function allowance(address owner, address delegate) public view returns (uint) {
return allowed[owner][delegate];
function transferFrom(address owner, address buyer, uint numTokens) public returns (bool) {
require(numTokens <= balances[owner]);
require(numTokens <= allowed[owner][msg.sender]);
balances[owner] = balances[owner].sub(numTokens);
allowed[owner][msg.sender] = allowed[owner][msg.sender].sub(numTokens);
balances[buyer] = balances[buyer].add(numTokens);
Transfer(owner, buyer, numTokens);
return true;
library SafeMath {
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
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Radmila56 commented Oct 21, 2020 via email

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can you update source for latest version of pragma solidity?

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lrod29 commented Apr 28, 2021

has Anyone a code for a deflationary token?

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has Anyone a code for a deflationary token?

@lrod29 Having a fixed maximum on your circulating supply should be enough to make a token deflationary. Fiats like USD are inflationary because the gov't is always printing it with no cap.

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towhid135 commented May 10, 2021

can you please suggest any article of yours where you showed how to transfer tokens to another address? And how to create another address to testing the transfer process.

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hi anybody can explaine what this soldity do ??

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Where exactly do you enter the total supply in the above?

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how to exchange real usdt token through smart contract,
can buy /sell,from usdt to "BSC" token?

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quakestreet commented Jan 24, 2022

how do i add logo to the coin thats created and will this code work for the bsc

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ghost commented Mar 5, 2022

Gotta change

  1. line no 46
    emit Approval(msg.sender, delegate, numTokens);
  2. line no 61
  3. line no 1
    pragma solidity ^0.4.19; -> This version doen't work.
    advised one -> pragma solidity >=0.4.22 <0.6.0;
    Thanks 👍
    what has to be done at line 61??

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tobbhie commented Mar 20, 2022

add emit

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