My 90's Stuff: Solving a 3X3 Rubik's Cube
This is a basic algorithm, taken from elsewhere from internet. My intent here is to provide a simplified format of the algorithm, using a minimal expression.
This solution solves the cube in three easy steps.
Notations
Each step has some tasks in it. Each task requieres some moves
to be made to bring the pieces to correct position and orientation. The moves
in the next sections will be described using the following notation.
Face notation: F=front face; U=top face; B=Back face;
R=right face; L=left face; D=bottom face
Piece / position notation: Example: FR=the edge piece
between the corner pieces UFR and DFR.
Move notation: F=90 deg clockwise for Front face; F'=90
deg counter clockwise; F2=180 deg.
For example, the move FDF'D'R'D'R means the following rotations (all 90 deg) in that sequence:
front face clockwise, bottom face clockwise, front face anti-clockwise,
bottom face anti-clockwise, right face anti-clockwise, bottom face anti-clockwise, right face clockwise.
Step 0. Solve the top layer
This step is the easiest and better done without help. The task list below is given as a hint. At the end of this step, the top face shoud also have matching colors with its sides.
Task 0.1: Get the cross - To get the four
edge pieces matching color with center and with sides.
Task 0.2: Position corner cubes - Get the corner
pieces in correct places. - Don't bother colors.
Task 0.3: Orient corner cubes - Rotate the cubes
to have matching colors - (See Task 2.4)
Step 1. Solve the middle layer
Task1.1: Position and orient the middle layer edge
pieces
State: The piece to be moved to FR or FL is at DB and has the 'F'
color on its D side.
Case1: Move it to FR : FDF'D'R'D'R
Case2: Move it to FL : F'D'FDLDL'
Case3 :If the piece is not on D face, apply any of the above
moves and go to Task 1.1.
Step 2. Solve the bottom layer
Turn the cube upside down; old D face now becomes U face. Forget the corner cubes for a while.
Task2.1: Get the cross
Case1: two opposite edge pieces have U color up marking a
straight band BLUL'U'B'
Case2: two adjacent edge pieces have U color up marking an
angular band BULU'L'B'
Case3: no edge pieces have U color up - apply any of the above
moves and go to Task 2.1
Task2.2: Rotate edge pieces
Case1: only UL is correctly placed, other pieces need clockwise
rotation - R2U2D'LR'F2RL'DR2
Case2: only UL is correctly placed, other pieces need counter
rotation R2D'LR'F2RL' - U2DR2
Case3: none or two opposite pieces are correctly positioned above
- apply any of the above moves and go to Task 2.2
Task2.3: Position corner cubes
Case1: only UFR is correctly placed, other pieces need clockwise
rotation - L'URU'LUR'U'
Case2: only UFR is correctly placed, other pieces need counter
rotation - URU'L'UR'U'L
Case3: none are correctly positioned - apply any of the above
moves and go to Task 2.3
Task2.4: Rotate corner cubes
State: All corner cubes are in correct places but some of them
may need rotation to match colors.
Apply one of the moves to rotate UFR, and rotate U face only to
bring the next piece to be rotated into UFR position.
Case1: Clockwise - FDF'D' FDF'D'
Case2: Counter - DFD'F'DFD'F'