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Order.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract A {
    function foo() public         pure returns (uint) { return bar(); }
    function bar() public virtual pure returns (uint) { return 1; }
}

contract B is A { }

contract C is B {

    // Q1 What is the output of C.main() ?
    function main() public pure returns (uint) { return foo(); }

    function bar() public override pure returns (uint) { return 2; }
}