First, Platini's question yesterday: 

        when I presented the description of a code by its 
        Parity-Check Matrix, for example, 

  H =  1 1 1 0 1 0 0
       0 1 1 1 0 1 0
       1 0 1 1 0 0 1

        Platini asked, "how is _decoding_ described, 
        from the viewpoint of the parity-check matrix?"

        This is a very good question, and I would like you 
        to think about it. It will probably help you with 
        your "invent an encoder and decoder" project!

        For example, take the noise vector 

       0 1 0 0 0 0 0

        and think about the decoding problem using the 
        'Venn diagram' approach, and think about the 
        syndrome and the parity check matrix.

Second, when I reminded you about the light-bulb question, 
        I intended to give you the following challenges:

        a) If all the bulbs are on, can you switch them
                all off? 

        b) Can you get from "all off" to "just one bulb 
                is on"?

        c) Can you get from "all off" to "two bulbs are on"?

	d) If switch number 1 stopped working, could you 
		_emulate_ switch 1's effect by 
		switching some of the other switches? 
		If switches 1 and 2 both stopped working, 
		could you still reach all the same states 
		by using the other switches? 

Is there a connection betweeen these two questions? 
Everything is connected!