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contracts...11_Inheritance2.sol

pragma solidity 0.5.11;

contract A {

  event Log(string message);

  function foo() public {
      emit Log("Contract A.foo was called");
  }

  function bar() public {
      emit Log("Contract A.bar was called");
  }
}


contract B is A {
    function foo() public {
        emit Log("Contract B.foo was called");
        A.foo();
    }

    function bar() public {
        emit Log("Contract B.bar was called");
        super.bar();
    }
}


contract C is A {
    function foo() public {
        emit Log("Contract C.foo was called");
        A.foo();
    }
  
    function bar() public {
        emit Log("Contract C.bar was called");
        super.bar();
    }

}

contract D is B, C {
    
}