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HelloWorld.sol - zku2022

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.10;

contract HelloWorld {
    // a variable to store a number
    uint public number;

    // function to store an unsigned integer
    function storeNumber(uint _number) public {
        number = _number;
    }

    // function to retrieve it an unsigned integer.
    function retrieveNumber() public view returns (uint) {
        return number;
    }
}