WEEK01: intro to python, unix, cs21
 M: Welcome to CS 21, about the course, etc

 - write lots of computer programs, learn some CS along the way
 - learn PYTHON programming language
 - labs/programs due every week
 - meant for students without any CS/programming experience

 - attending lab sessions and ninja sessions is optional
 - you can also go to any lab session you want


    can you solve rubik's cube?   http://www.rubiks.com
    can you write out a list of step-by-step instructions that
    anyone could follow, that would allow them to solve rubik's cube??

    an algorithm is like a recipe or list of instructions to follow

    Here's an algorithm for solving rubik's cube:

rubik's cube algorithm

    is it the "best" algorithm??
    what do we mean by "best"??
    is it the fastest algorithm?
    is it the simplest algorithm?
    is it in a form that the computer could understand?


    if I were writing a computer program to play the game of 
    tic-tac-toe (with a user), here's what it might look like:

  draw the empty board
  keep doing this over and over:
    ask user to choose a spot
    draw user's mark on board
    check if the game is over: if yes, go to "print winner" line below
    computer picks spot
    draw computer's mark on board
    check if the game is over: if yes, go to "print winner" line below
    go back to "ask user" line above  
  print the winner, game over...
    can you think up an algorithm that the 
    computer could follow to pick it's spot???
    how do we "check if the game is over"???

    what do we ask the user to input to choose their spot??
    a number? some text ("upper left")?

    notice that the above pseudo-code only has 4 basic components:
      INPUT     (ask user to choose...)
      OUTPUT    (draw board, draw mark on board, print winner)
      LOOPING   (keep doing this over and over...)
      BRANCHING (if game over, go to ...)

    the tic-tac-toe program will also need a DATA STRUCTURE: some
    way to represent the board and it's current state (which spots
    are taken and what marks are in those spots). the ALGORITHM
    ties it all together.
    intro to cs, learning to program, learn to develop and
    analyze algorithms (lots of problem solving)

    who should you take this course: students new to CS and programming
    (if you've already done some programming, CS31 or CS35 might be
     better for you)

    what to expect
      - class builds on previous week's work
      - does require work (lab time)
      - help is available (ninjas)...but START EARLY
      - my teaching style (learn by doing)
      - why python?
    unix login and first python program (print "hello")
        - cs account
        - let me know if name not correct
        - prox tags
        - passwd 
        - dock and terminal program and unix prompt
        - logging out, ssh access (putty, mac)

    LAB0: vimtutor, using unix, update21, handin21