twitterGame-1

twitterGameOne.sol

pragma solidity ^0.8.0;

contract A {

    address systemAddress;

    function setSystemAddress(address systemAddress_) public {
        systemAddress = systemAddress_;
    }

    function fromSystem(address from) public view {
        require(
            from == systemAddress,
            "Invalid transaction source"
        );
    }
}

contract B {

    uint[] data;
    A a;

    constructor(address contractAddress){
        data.push(10);
        a = A(contractAddress);
    }

    modifier fromSystem() {
        a.fromSystem(msg.sender);
        _;
    }

    function funcB() public returns (uint[] memory){
        data.push(20);
        return data;
    }

    function setData(uint value) public fromSystem {
        data.push(value);
    }
}

contract C {

    A a;
    B b;

    constructor(address contractAddressA, address contractAddressB){
        a = A(contractAddressA);
        b = B(contractAddressB);
    }

    modifier fromSystem() {
        a.fromSystem(msg.sender);
        _;
    }

    function funcC() public fromSystem returns (uint[] memory){
        return b.funcB();
    }
}