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contracts...9_Constructor.sol

pragma solidity 0.8.11;

contract Constructor {
    uint public a;
    string public b;
    address public owner;
    uint public createdAt; 

    constructor(uint _a, string memory _b) {
        a = _a;
        b = _b;
        owner = msg.sender;
        createdAt = block.timestamp;
    }
}