Use the following smart contract in the code editor of your choice, customise your cryptocurrency, and compile your code after approving the connection using your preferred digital wallet (here, MetaMask Wallet is used).
Copy // SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.16;
interface IERC20 {
event Transfer ( address indexed from, address indexed to, uint256 value);
event Approval ( address indexed owner, address indexed spender, uint256 value);
function totalSupply () external view returns ( uint256 );
function balanceOf ( address account) external view returns ( uint256 );
function transfer ( address to , uint256 amount) external returns ( bool );
function allowance ( address owner , address spender) external view returns ( uint256 );
function approve ( address spender , uint256 amount) external returns ( bool );
function transferFrom ( address from , address to , uint256 amount) external returns ( bool );
}
contract SampleERC20Token is IERC20 {
string public symbol;
string public name;
uint8 public decimals;
uint public _totalSupply;
mapping ( address => uint ) balances;
mapping ( address => mapping ( address => uint )) allowed;
constructor () {
symbol = "SYM" ;
name = "Sample ERC20 Token" ;
decimals = 2 ;
_totalSupply = 100000 ;
balances[msg.sender] = _totalSupply;
emit Transfer ( address ( 0 ) , msg.sender , _totalSupply);
}
function totalSupply () external view returns ( uint ) {
return _totalSupply - balances[ address ( 0 )];
}
function balanceOf ( address tokenOwner) external view returns ( uint balance) {
return balances[tokenOwner];
}
function transfer ( address to , uint tokens) public returns ( bool success) {
balances[msg.sender] = balances[msg.sender] - tokens;
balances[to] = balances[to] + tokens;
emit Transfer (msg.sender , to , tokens);
return true ;
}
function approve ( address spender , uint tokens) public 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 returns ( bool success) {
balances[from] = balances[from] - tokens;
allowed[from][msg.sender] = allowed[from][msg.sender] - tokens;
balances[to] = balances[to] + tokens;
emit Transfer (from , to , tokens);
return true ;
}
function allowance ( address tokenOwner , address spender) external view returns ( uint remaining) {
return allowed[tokenOwner][spender];
}
}