contract.sol

pragma solidity ^0.4.2;
contract owned {
    address public owner;

    function owned() {
        owner = msg.sender;
    }

    modifier onlyOwner {
        if (msg.sender != owner) throw;
        _;
    }

    function transferOwnership(address newOwner) onlyOwner {
        owner = newOwner;
    }
}

contract tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData); }

contract token {
    /* Public variables of the token */
    string public standard = 'Token 0.1';
    string public name;
    string public symbol;
    uint8 public decimals;
    uint256 public totalSupply;

    /* This creates an array with all balances */
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;

    /* This generates a public event on the blockchain that will notify clients */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /* Initializes contract with initial supply tokens to the creator of the contract */
    function token(
        uint256 initialSupply,
        string tokenName,
        uint8 decimalUnits,
        string tokenSymbol
        ) {
        balanceOf[msg.sender] = initialSupply/2;            // Give the creator half initial tokens
        balanceOf[this] = initialSupply/2;                  // Give the contact half initial tokens
        totalSupply = initialSupply;                        // Update total supply
        name = tokenName;                                   // Set the name for display purposes
        symbol = tokenSymbol;                               // Set the symbol for display purposes
        decimals = decimalUnits;                            // Amount of decimals for display purposes
    }

    /* Send coins */
    function transfer(address _to, uint256 _value) {
        if (balanceOf[msg.sender] < _value) throw;           // Check if the sender has enough
        if (balanceOf[_to] + _value < balanceOf[_to]) throw; // Check for overflows
        balanceOf[msg.sender] -= _value;                     // Subtract from the sender
        balanceOf[_to] += _value;                            // Add the same to the recipient
        Transfer(msg.sender, _to, _value);                   // Notify anyone listening that this transfer took place
    }

    /* Allow another contract to spend some tokens in your behalf */
    function approve(address _spender, uint256 _value)
        returns (bool success) {
        allowance[msg.sender][_spender] = _value;
        return true;
    }

    /* Approve and then communicate the approved contract in a single tx */
    function approveAndCall(address _spender, uint256 _value, bytes _extraData)
        returns (bool success) {
        tokenRecipient spender = tokenRecipient(_spender);
        if (approve(_spender, _value)) {
            spender.receiveApproval(msg.sender, _value, this, _extraData);
            return true;
        }
    }

    /* A contract attempts to get the coins */
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
        if (balanceOf[_from] < _value) throw;                 // Check if the sender has enough
        if (balanceOf[_to] + _value < balanceOf[_to]) throw;  // Check for overflows
        if (_value > allowance[_from][msg.sender]) throw;   // Check allowance
        balanceOf[_from] -= _value;                          // Subtract from the sender
        balanceOf[_to] += _value;                            // Add the same to the recipient
        allowance[_from][msg.sender] -= _value;
        Transfer(_from, _to, _value);
        return true;
    }

    /* This unnamed function is called whenever someone tries to send ether to it */
    function () {
        throw;     // Prevents accidental sending of ether
    }
}

contract MyAdvancedToken is owned, token {

    uint256 public sellPrice = 100000000000000;             // price in Wei
    uint256 public buyPrice = 100000000000000;

    mapping (address => bool) public frozenAccount;

    /* This generates a public event on the blockchain that will notify clients */
    event FrozenFunds(address target, bool frozen);

    /* Initializes contract with initial supply tokens to the creator of the contract */
    function MyAdvancedToken(
        uint256 initialSupply,
        string tokenName,
        uint8 decimalUnits,
        string tokenSymbol
    ) token (initialSupply, tokenName, decimalUnits, tokenSymbol) {}

    /* Send coins */
    function transfer(address _to, uint256 _value) {
        if (balanceOf[msg.sender] < _value) throw;           // Check if the sender has enough
        if (balanceOf[_to] + _value < balanceOf[_to]) throw; // Check for overflows
        if (frozenAccount[msg.sender]) throw;                // Check if frozen
        balanceOf[msg.sender] -= _value;                     // Subtract from the sender
        balanceOf[_to] += _value;                            // Add the same to the recipient
        Transfer(msg.sender, _to, _value);                   // Notify anyone listening that this transfer took place
    }


    /* A contract attempts to get the coins */
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
        if (frozenAccount[_from]) throw;                        // Check if frozen
        if (balanceOf[_from] < _value) throw;                 // Check if the sender has enough
        if (balanceOf[_to] + _value < balanceOf[_to]) throw;  // Check for overflows
        if (_value > allowance[_from][msg.sender]) throw;   // Check allowance
        balanceOf[_from] -= _value;                          // Subtract from the sender
        balanceOf[_to] += _value;                            // Add the same to the recipient
        allowance[_from][msg.sender] -= _value;
        Transfer(_from, _to, _value);
        return true;
    }

    function mintToken(address target, uint256 mintedAmount) onlyOwner {
        balanceOf[target] += mintedAmount;
        totalSupply += mintedAmount;
        Transfer(0, this, mintedAmount);
        Transfer(this, target, mintedAmount);
    }

    function freezeAccount(address target, bool freeze) onlyOwner {
        frozenAccount[target] = freeze;
        FrozenFunds(target, freeze);
    }

    function setPrices(uint256 newSellPrice, uint256 newBuyPrice) onlyOwner {
        sellPrice = newSellPrice;
        buyPrice = newBuyPrice;
    }

    function buy() payable {
        uint amount = msg.value / buyPrice;                // calculates the amount
        if (balanceOf[this] < amount) throw;               // checks if it has enough to sell
        balanceOf[msg.sender] += amount;                   // adds the amount to buyer's balance
        balanceOf[this] -= amount;                         // subtracts amount from seller's balance
        Transfer(this, msg.sender, amount);                // execute an event reflecting the change
    }

    function sell(uint256 amount) {
        if (balanceOf[msg.sender] < amount ) throw;        // checks if the sender has enough to sell
        balanceOf[this] += amount;                         // adds the amount to owner's balance
        balanceOf[msg.sender] -= amount;                   // subtracts the amount from seller's balance
        if (!msg.sender.send(amount * sellPrice)) {        // sends ether to the seller. It's important
            throw;                                         // to do this last to avoid recursion attacks
        } else {
            Transfer(msg.sender, this, amount);            // executes an event reflecting on the change
        }
    }
}

contract SimpleFairLottery is MyAdvancedToken {
    uint public countTickets = 100;
    uint public availableTickets = countTickets;
    uint public JackPot = 0;
    address[100] public tickets;
    uint public ticketPrice = 10;                           // ticket price in tokens
    uint public toJackPotfromEveryTicket = 4;
    uint public xPrize = 4;
    uint public lastWinNumber;

    function clearTickets() {
        availableTickets = countTickets;
        for (uint i = 0 ; i < countTickets ; i++ )
            tickets[i] = 0;
    }

    function SimpleFairLottery(
    ) MyAdvancedToken (countTickets*ticketPrice*10, "Simple Fair Lottery", 0, "SLT") {  // initial supply is 10000 tokens
        clearTickets();
    }

    function buyTicket(uint ticketNum) returns (bool success)  {
        uint index = ticketNum - 1;
        if ( (index < 0) || (index >= countTickets)) return false;  // Check if the number is right
        if (balanceOf[msg.sender] < ticketPrice) return false;              // Check if the sender has enough
        if ( tickets[index] != 0 ) return false;                        // Check if ticket already buyed
        balanceOf[msg.sender] -= ticketPrice;                               // take ticket price from sender
        balanceOf[this] += ticketPrice;                                     // send ticket price to contract address
        JackPot += toJackPotfromEveryTicket;                                // send tokens to JackPot
        tickets[index] = msg.sender;                                    // write senders address to ticketlist
        availableTickets -= 1;
        return true;
    }

    function play() onlyOwner {
        lastWinNumber = uint(block.blockhash(block.number-1))%countTickets + 1;         // take random number from 0 to 99
        if (tickets[lastWinNumber] !=0 ){                                               // if someone win a JackPot
            balanceOf[tickets[lastWinNumber]] += JackPot;                               // send all JackPot for him
            JackPot = 0;                                                                // and clear JackPot
        }
        uint i1 = lastWinNumber - (lastWinNumber%10);
        for (uint i = i1 ; i < i1 + 10 ; i++)                                           // send tockens for every small winner
            balanceOf[tickets[i]] += ticketPrice * xPrize;

        clearTickets();
    }

    function setLotteryParameters(uint newTicketPrice, uint newToJackPotfromEveryTicket, uint newXPrize) onlyOwner {
        ticketPrice = newTicketPrice;
        toJackPotfromEveryTicket = newToJackPotfromEveryTicket;
        xPrize = newXPrize;
    }


}