Machine_interface.sol

pragma solidity ^0.5.8;

interface StorageInterface {
    function saveValue(uint x) public returns (bool);
}

contract Machine {
    StorageInterface public s;
    
    constructor(StorageInterface addr) public {
        s = addr;
        calculateResult = 0;
    }
    
    function saveValue(uint x) public returns (bool) {
        s.setValue(x);
        return true;
    }
    
    function getValue() public view returns (uint) {
        return s.val();
    }
}