coin

pragma solidity >=0.5.0 <0.7.0;

contract Coin {

    address public minter;

    mapping (address =>uint) public balances;

    event Sent(address from, address to, uint amount);

    constructor() public{

        minter =msg.sender;

    }

    function mint(address receiver,uint amount) public {

        require(msg.sender == minter);

        require(amount<1e60);

        balances[receiver]+=amount;

        emit Sent(msg.sender, receiver, amount);

    }

    function send(address receiver, uint amount) public {

        require(amount <=balances[msg.sender],"Insufficient balance.");

        balances[msg.sender] -=amount;

        balances[receiver]+=amount;

        emit Sent(msg.sender, receiver, amount);

    }

}