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// SPDX-License-Identifier: Unlicense
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pragma solidity ^0.8.17;
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import {IPuzzle} from "../interfaces/IPuzzle.sol";
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/// @title 0xF1A9
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/// @author fiveoutofnine
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contract F1A9 is IPuzzle {
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    /// @inheritdoc IPuzzle
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    function name() external pure returns (string memory) {
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        return "0xF1A9";
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    }
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    /// @inheritdoc IPuzzle
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    function generate(address _seed) external view returns (uint256) {
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        return (uint256(uint160(_seed)) >> (((block.number >> 8) & 0x1F) << 2)) & 0xFFFF;
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    }
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    /// @inheritdoc IPuzzle
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    function verify(uint256 _start, uint256 _solution) external returns (bool) {
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        uint256 prefix = block.timestamp < 1678446000
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            ? (0xF1A9 << 16) | _start
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            : 0;
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        return
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            prefix == (_solution >> 128) &&
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            ISolve(address(uint160(_solution))).curtaPlayer() == msg.sender;
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    }
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}
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interface ISolve {
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    function curtaPlayer() external pure returns (address);
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}
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