How to Solve 3x3 Slide Puzzle

• As part of the confirmation for the 6th anniversary events, you will be solving slide puzzle.
• After seeing our DFO team struggle on their stream, here's the strategy and step-by-step on how to solve this.

Basic Information

• Sliding puzzle, 3x3 as example, is basically a puzzle where it only gives you 1 empty space out of the 9 slots.
• You have to slide the pieces around to create the complete picture.
• If you think about it. There are 8 pieces to move around, but you really only need to put 5 pieces in the correct slots, the rest will fall into place.
• Before we start, here's an example of me solving a similar puzzle. You can try it in this link.

Golden Rule

• Remember this, put the pieces IN THE ORDER of how you plan to rotate them.
• You will understand when I show you how to solve this.

Main Strategy

• Below is an example of a puzzle, using West Coast art. This image was created using https://puzzel.org/

• First: Complete a row (must not be the middle row). In my example, I finish top row first.
• Second: Complete a column (must not be the middle column). In my example, I did the left column. (If you think about it, the 1st piece of your column is already done, so you only have to correct 2 pieces).
• Third: Done, nothing to do left, the remaining pieces should fall into place when you rotate them enough times.

Step-by-Step

• Step 1: Move the 1st piece to the corner

• Step 2: Move the other 2 pieces to complete the top row. 

• As you can see, there's no way you can correctly place them one-by-one. You simply just don't have the space. So in order to do this you need to move them in the order of your rotation (GOLDEN RULE). Then when you rotate, everything will fall into place.

• Look at the demonstration below. I put the correct right corner piece (1) in the middle of the top row. Then I put the correct middle piece of the top row (2) in the center of the puzzle.
• So after I rotate both pieces, they're now in the correct location.

• Step 3: Complete the left column. As you can see, the top piece already in place, so all you need is the other 2 pieces.

• This part is even trickier because the space you have to work with is even smaller.
• In order to combat this small space, what you needs to do is to sperate the 2 pieces away from each other (ie. one stay in left column, one stay in right column).
• Look at the example below, on the left picture, I put piece (1) on the right column so I can freely rotate piece (2).
• Once piece (2) is in place, on the right picture, I can freely rotate piece (1).

• Again, applying the GOLDEN RULE, when the 2 pieces are in order, rotate them again, and they will be in the correct location.

• Step 4: You're done, just rotate the remaining pieces. Like I said before, these last ones ALWAYS come into place.

• That's it. Easy and simple, right? Just practice or be like the Internet said, Git Gud.