
This method to solve is very slow, but you only to use less than 10 simple formulas to solve many kinds of cubes (from 2x2x2 to 5x5x5).
1.solve bottom and layer1
2.solve the corner of layer2
3.solve the middle of layer2
4.solve the corner and the frame of top
5.solve the corner of layer3
6.solve the unfinished part of middle