60 lines
1.5 KiB
Solidity
60 lines
1.5 KiB
Solidity
pragma solidity 0.4.18;
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import "./Token_v2.sol";
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contract ERC20Token is Token_v2 {
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function transfer(address _to, uint _value)
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public
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returns (bool)
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{
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require(balances[msg.sender] >= _value && balances[_to] + _value >= balances[_to]);
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balances[msg.sender] -= _value;
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balances[_to] += _value;
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Transfer(msg.sender, _to, _value);
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return true;
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}
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function transferFrom(address _from, address _to, uint _value)
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public
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returns (bool)
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{
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require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value && balances[_to] + _value >= balances[_to]);
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balances[_to] += _value;
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balances[_from] -= _value;
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allowed[_from][msg.sender] -= _value;
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Transfer(_from, _to, _value);
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return true;
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}
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function approve(address _spender, uint _value)
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public
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returns (bool)
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{
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allowed[msg.sender][_spender] = _value;
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Approval(msg.sender, _spender, _value);
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return true;
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}
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function balanceOf(address _owner)
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public
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view
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returns (uint)
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{
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return balances[_owner];
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}
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function allowance(address _owner, address _spender)
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public
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view
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returns (uint)
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{
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return allowed[_owner][_spender];
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}
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mapping (address => uint) balances;
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mapping (address => mapping (address => uint)) allowed;
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uint public totalSupply;
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}
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