User:Arjun sunel/sandbox

Blindfold Rubik's Cube
I know most of you may be afraid of even thinking about how one can solve a rubik's cube with his eyes closed.So, for your kind information, let me tell you that it is not so much difficult as people think of. It just requires some memorization and a lot of patience. I, too was scared about it in the beginning. But, I continuously tried hard for blindfold solving and I was able to learn this method in just 2 days. Now, I can solve it blindfolded. My first successful blindfolded solve took about 25 minutes. But, before you start trying blindfold cubing, you must know how to solve the rubik's cube with your eyes opened and should be able to solve it under 2 minutes.If you do not fulfill above prerequisites, then I strongly recommend you to learn basic cubing first. Now, lets come to the point. The most difficult thing one faces in blindfold solving is to memorize the initial state of the cube. You will have to memorize around 26 things about the initial state of the cube in the worst case. I will teach you about the method of blind-solving in 3 steps which covers: -->How to memorize the cube? -->How to solve the cube with your eyes closed? Assumptions: In my whole discussion, I will assume holding the cube as follows: CENTRE                                           POSITION YELLOW                                              TOP WHITE                                                BOTTOM BLUE                                                  FRONT GREEN                                               BACK RED                                                   RIGHT ORANGE                                            LEFT Memorization techniques: CORNER PIECE                       NUMBER ASSIGNED Note: Here each letter in the first column defines a position TLB                                                    1 TRB                                                    2 TLF                                                    3 TRF                                                   4 BLB                                                   5 BRB                                                   6 BLF                                                   7 BRF                                                   8 EDGE PIECE                      LETTER ASSIGNED Note: Here each letter in the first column defines a colour YB                                            a       BY                                             b                                YG                                             c       GY                                             d       YR                                              e       RY                                              f       YB                                              g       BY                                              h       GO                                             i       OG                                             j       OB                                             k       BO                                             l       BR                                             m       RB                                             n       RG                                             o       GR                                             p       WO                                            q       OW                                            r       WB                                            s       BW                                            t       WR                                            u       RW                                            v       WG                                            w       GW                                            x      NOTATIONS FOR ROTATION OF CORNERS: CLOCKWISE                    + (plus) ANTI-CLOCKWISE            -  (minus) Step1: First of all, as I discussed above, hold the cube accordingly. Now, our first aim will be to make the top or bottom stickers of all the 8 corners either White or yellow colored. Now, imagine that you are holding a corner piece in your pinch; so, how will you rotate the piece (clockwise or anti-clockwise) only once, so that either white or yellow sticker will come on the bottom or top face. Give + sign to that corner if it needs to be turned clockwise and - (minus) sign if it needs to be turned anti-clockwise.If the corner is already correctly placed, then no need to memorize it ie. ignore it. Example: 2+, 3- Meaning: Corner 2 needs to be rotated clockwise to bring either white or yellow sticker on the Top or bottom. Note: Position 1 will be used as undisturbed zone and position 3 will be used as buffer zone here. For achieving our first goal, bring the corner to be rotated, in buffer zone; keeping in mind that undisturbed zone should never be disturbed or moved or rotated. So, we cannot rotate L, U and B faces here. After bringing the corner piece in buffer position, apply required one of the two algorithms described as under and bring the corner back to the previous position using just the reverse steps as you used for bringing it in buffer position. Algorithm for Rotating Clockwise: RUR'U' RUR'U' L' URU'R' URU'R' L Algorithm for Rotating Anti - Clockwise: URU'R' URU'R' L' RUR'U' RUR'U' L  Step2:  Placing the corners correctly: You will see that after doing Step1, all corner pieces will have either white or yellow sticker on the top or bottom side. You will also notice that they all may not be "placed correctly". Example : Let the corner be GRY colored ie. it mean that it has 3 stickers  having colors Green, Red and Yellow. Therefore, if this corner is not placed at  the intersection of the faces having G, R and Y as center pieces, then it is not correctly placed. Note: Here position 2 will be undisturbed zone and 4 will be the buffer zone. Also, note that we can move only L, F, M , m faces. where M = vertical middle layer m = horizontal middle layer Now, see the corner piece in the undisturbed zone and to place the corner correctly, bring that corner piece in the buffer position where the corner piece of undisturbed zone has to go and apply the algorithm as under and bring the corner back to the previous position using steps just reverse as that used for bringing it in the buffer position. If the corner piece in the undisturbed zone is correctly placed, but not all the corners are correctly placed; then move that corner piece to any unsolved corner. As a result, an incorrect corner piece will come in undisturbed zone; so continue the above process until all the corner pieces are correctly placed. Algorithm :           R'U2RUR'U2LU'RUL' USE: This algorithm swaps the corner pieces of undisturbed zone and buffer zone and also swaps the two edges on the top face in neighborhood of undisturbed zone. For memorizing about placing the corners, use numbering the corners as mentioned in the Notation part above. Example: (1,3,5) + 4 + ( 6, 4) rubik Meaning: Use this method to  memorize  for placing the corner pieces correctly. Initially (after Step1 has been executed), the corner piece in undisturbed zone needs to go in position 1; now the piece in position 1 needs to go in position 3; then the piece in position 3 needs to go in position 5. Now the cycle is closed meaning that the piece in position 5 has gone to undisturbed zone and is correctly placed. But, since all the corner pieces have not been placed correctly, therefore, we move the piece in undisturbed zone to any unsolved corner position say 4. Now, the piece in position 4 needs to go in position 6 ; then the piece in position 6 needs to go in position 4 and the piece in position 4 needs to in position 2 ie. undisturbed zone. Since, positions 7 and 8 were not taken account simply means that they were already correctly placed. Step3: Placing the edges correctly:

Note: Here, the undisturbed zone will be the edge between the buffer zone and undisturbed zone of the corners. The other edge which gets swapped with this edge will become the buffer zone.

Here, also follow the same method as that used for placing the edges correctly. The only difference is that now our cycles will consists of letters instead of numbers. Each time, see where the sticker in the undisturbed zone should go; bring the sticker of that position in the buffer zone, do the algorithm, which will swap the two edges; and then bring the edge back to its previous position; which places the edge piece correctly. Cycle breaking method will be the same as discussed above. Example: (m) + c + ( q, h, a , o , i , x , d ) Best of Luck !!!!!!!!!!!!!!!!!!!!!!!!! With Regards, Arjun Sunel rubik