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// SPDX-License-Identifier: MIT
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pragma solidity ^0.8.18;
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interface IStarknetCore {
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    function consumeMessageFromL2(uint256, uint256[] calldata)
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        external
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        returns (bytes32);
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}
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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// ping pong ping pong ping pong ping pong ping pong ping pong ping pong ping pong
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/// @title PingPong
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/// @author exp.table
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contract PingPong {
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    IStarknetCore constant starknetCore = IStarknetCore(0xc662c410C0ECf747543f5bA90660f6ABeBD9C8c4);
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    uint256 constant pong = 0x012d8ab4947254afb512883d7d768d17436c9057a1ae21e53389603266c397f7;
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    address a;
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    constructor(bytes memory bytecode) {
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        assembly {
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            sstore(a.slot, create(0, add(bytecode, 0x20), mload(bytecode)))
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        }
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    }
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    function name() external pure returns (string memory) {
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        return "Ping Pong";
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    }
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    function generate(address _seed) external view returns (uint256) {
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        return uint256(keccak256(abi.encodePacked(_seed, block.number)));
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    }
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    function verify(uint256 _start, uint256 _solution) external returns (bool success) {
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        uint256[] memory payload = new uint256[](3);
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        payload[0] = _start >> 128;
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        payload[1] = _start & 340282366920938463463374607431768211455;
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        payload[2] = _solution;
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        starknetCore.consumeMessageFromL2(pong, payload);
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        (, bytes memory result) = a.call(abi.encode(_solution));
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        success = abi.decode(result, (bool));
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    }
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    function gist() external pure returns (string memory) {
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        return "9761e3575eb6439a1fab1d834ddc18aa";
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    }
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}