/**
* Generates a random cube.
* @return A random cube in the string representation. Each cube of the cube space has the same probability.
*/
public static String randomCube()
{
CubieCube cc = new CubieCube();
Random gen = new Random();
cc.setFlip((short)gen.Next(CoordCube.N_FLIP));
cc.setTwist((short)gen.Next(CoordCube.N_TWIST));
do
{
cc.setURFtoDLB(gen.Next(CoordCube.N_URFtoDLB));
cc.setURtoBR(gen.Next(CoordCube.N_URtoBR));
} while ((cc.edgeParity() ^ cc.cornerParity()) != 0);
FaceCube fc = cc.toFaceCube();
return(fc.to_String());
}
static CoordCube()
{
if (LoadPrunData())
{
return;
}
// ******************************************Phase 1 move tables*****************************************************
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for the twists of the corners
// twist < 2187 in phase 2.
// twist = 0 in phase 2.
CubieCube a = new CubieCube();
for (short i = 0; i < N_TWIST; i++)
{
a.setTwist(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.cornerMultiply(CubieCube.moveCube[j]);
twistMove[i, 3 * j + k] = a.getTwist();
}
a.cornerMultiply(CubieCube.moveCube[j]); // 4. faceturn restores
// a
}
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for the flips of the edges
// flip < 2048 in phase 1
// flip = 0 in phase 2.
a = new CubieCube();
for (short i = 0; i < N_FLIP; i++)
{
a.setFlip(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.edgeMultiply(CubieCube.moveCube[j]);
flipMove[i, 3 * j + k] = a.getFlip();
}
a.edgeMultiply(CubieCube.moveCube[j]);
// a
}
}
// ***********************************Phase 1 and 2 movetable********************************************************
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for the four UD-slice edges FR, FL, Bl and BR
// FRtoBRMove < 11880 in phase 1
// FRtoBRMove < 24 in phase 2
// FRtoBRMove = 0 for solved cube
a = new CubieCube();
for (short i = 0; i < N_FRtoBR; i++)
{
a.setFRtoBR(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.edgeMultiply(CubieCube.moveCube[j]);
FRtoBR_Move[i, 3 * j + k] = a.getFRtoBR();
}
a.edgeMultiply(CubieCube.moveCube[j]);
}
}
// *******************************************Phase 1 and 2 movetable************************************************
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for permutation of six corners. The positions of the DBL and DRB corners are determined by the parity.
// URFtoDLF < 20160 in phase 1
// URFtoDLF < 20160 in phase 2
// URFtoDLF = 0 for solved cube.
a = new CubieCube();
for (short i = 0; i < N_URFtoDLF; i++)
{
a.setURFtoDLF(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.cornerMultiply(CubieCube.moveCube[j]);
URFtoDLF_Move[i, 3 * j + k] = a.getURFtoDLF();
}
a.cornerMultiply(CubieCube.moveCube[j]);
}
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for the permutation of six U-face and D-face edges in phase2. The positions of the DL and DB edges are
// determined by the parity.
// URtoDF < 665280 in phase 1
// URtoDF < 20160 in phase 2
// URtoDF = 0 for solved cube.
a = new CubieCube();
for (short i = 0; i < N_URtoDF; i++)
{
a.setURtoDF(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.edgeMultiply(CubieCube.moveCube[j]);
URtoDF_Move[i, 3 * j + k] = (short)a.getURtoDF();
// Table values are only valid for phase 2 moves!
// For phase 1 moves, casting to short is not possible.
}
a.edgeMultiply(CubieCube.moveCube[j]);
}
}
// **************************helper move tables to compute URtoDF for the beginning of phase2************************
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for the three edges UR,UF and UL in phase1.
a = new CubieCube();
for (short i = 0; i < N_URtoUL; i++)
{
a.setURtoUL(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.edgeMultiply(CubieCube.moveCube[j]);
URtoUL_Move[i, 3 * j + k] = a.getURtoUL();
}
a.edgeMultiply(CubieCube.moveCube[j]);
}
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Move table for the three edges UB,DR and DF in phase1.
a = new CubieCube();
for (short i = 0; i < N_UBtoDF; i++)
{
a.setUBtoDF(i);
for (int j = 0; j < 6; j++)
{
for (int k = 0; k < 3; k++)
{
a.edgeMultiply(CubieCube.moveCube[j]);
UBtoDF_Move[i, 3 * j + k] = a.getUBtoDF();
}
a.edgeMultiply(CubieCube.moveCube[j]);
}
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Table to merge the coordinates of the UR,UF,UL and UB,DR,DF edges at the beginning of phase2
// for i, j <336 the six edges UR,UF,UL,UB,DR,DF are not in the
// UD-slice and the index is <20160
for (short uRtoUL = 0; uRtoUL < 336; uRtoUL++)
{
for (short uBtoDF = 0; uBtoDF < 336; uBtoDF++)
{
MergeURtoULandUBtoDF[uRtoUL, uBtoDF] = (short)CubieCube.getURtoDF(uRtoUL, uBtoDF);
}
}
// ****************************************Pruning tables for the search*********************************************
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Pruning table for the permutation of the corners and the UD-slice edges in phase2.
// The pruning table entries give a lower estimation for the number of moves to reach the solved cube.
for (int i = 0; i < N_SLICE2 * N_URFtoDLF * N_PARITY / 2; i++)
{
Slice_URFtoDLF_Parity_Prun[i] = -1;
}
int depth = 0;
setPruning(Slice_URFtoDLF_Parity_Prun, 0, 0);
int done = 1;
while (done != N_SLICE2 * N_URFtoDLF * N_PARITY)
{
for (int i = 0; i < N_SLICE2 * N_URFtoDLF * N_PARITY; i++)
{
int parity = i % 2;
int URFtoDLF = (i / 2) / N_SLICE2;
int slice = (i / 2) % N_SLICE2;
if (((i % 2 == 0) ? (Slice_URFtoDLF_Parity_Prun[i >> 1] & 0x0f) : ((Slice_URFtoDLF_Parity_Prun[i >> 1] & 0xf0) >> 4)) == depth)
{
for (int j = 0; j < 18; j++)
{
switch (j)
{
case 3:
case 5:
case 6:
case 8:
case 12:
case 14:
case 15:
case 17:
continue;
default:
int newSlice = FRtoBR_Move[slice, j];
int newURFtoDLF = URFtoDLF_Move[URFtoDLF, j];
int newParity = parityMove[parity][j];
int index = (N_SLICE2 * newURFtoDLF + newSlice) * 2 + newParity;
if (((index % 2 == 0) ? (Slice_URFtoDLF_Parity_Prun[index >> 1] & 0x0f) : ((Slice_URFtoDLF_Parity_Prun[index >> 1] & 0xf0) >> 4)) == 0x0f)
{
setPruning(Slice_URFtoDLF_Parity_Prun, (N_SLICE2 * newURFtoDLF + newSlice) * 2 + newParity,
(sbyte)(depth + 1));
done++;
}
break;
}
}
}
}
depth++;
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Pruning table for the permutation of the edges in phase2.
// The pruning table entries give a lower estimation for the number of moves to reach the solved cube.
for (int i = 0; i < N_SLICE2 * N_URtoDF * N_PARITY / 2; i++)
{
Slice_URtoDF_Parity_Prun[i] = -1;
}
depth = 0;
setPruning(Slice_URtoDF_Parity_Prun, 0, 0);
done = 1;
while (done != N_SLICE2 * N_URtoDF * N_PARITY)
{
for (int i = 0; i < N_SLICE2 * N_URtoDF * N_PARITY; i++)
{
int parity = i % 2;
int URtoDF = (i / 2) / N_SLICE2;
int slice = (i / 2) % N_SLICE2;
if (((i % 2 == 0) ? (Slice_URtoDF_Parity_Prun[i >> 1] & 0x0f) : ((Slice_URtoDF_Parity_Prun[i >> 1] & 0xf0) >> 4)) == depth)
{
for (int j = 0; j < 18; j++)
{
switch (j)
{
case 3:
case 5:
case 6:
case 8:
case 12:
case 14:
case 15:
case 17:
continue;
default:
int newSlice = FRtoBR_Move[slice, j];
int newURtoDF = URtoDF_Move[URtoDF, j];
int newParity = parityMove[parity][j];
int index = (N_SLICE2 * newURtoDF + newSlice) * 2 + newParity;
if (((index % 2 == 0) ? (Slice_URtoDF_Parity_Prun[index >> 1] & 0x0f) : ((Slice_URtoDF_Parity_Prun[index >> 1] & 0xf0) >> 4)) == 0x0f)
{
setPruning(Slice_URtoDF_Parity_Prun, (N_SLICE2 * newURtoDF + newSlice) * 2 + newParity,
(sbyte)(depth + 1));
done++;
}
break;
}
}
}
}
depth++;
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Pruning table for the twist of the corners and the position (not permutation) of the UD-slice edges in phase1
// The pruning table entries give a lower estimation for the number of moves to reach the H-subgroup.
for (int i = 0; i < N_SLICE1 * N_TWIST / 2 + 1; i++)
{
Slice_Twist_Prun[i] = -1;
}
depth = 0;
setPruning(Slice_Twist_Prun, 0, (sbyte)0);
done = 1;
while (done != N_SLICE1 * N_TWIST)
{
for (int i = 0; i < N_SLICE1 * N_TWIST; i++)
{
int twist = i / N_SLICE1, slice = i % N_SLICE1;
if (((i % 2 == 0) ? (Slice_Twist_Prun[i >> 1] & 0x0f) : ((Slice_Twist_Prun[i >> 1] & 0xf0) >> 4)) == depth)
{
for (int j = 0; j < 18; j++)
{
int newSlice = FRtoBR_Move[slice * 24, j] / 24;
int newTwist = twistMove[twist, j];
int index = N_SLICE1 * newTwist + newSlice;
if (((index % 2 == 0) ? (Slice_Twist_Prun[index >> 1] & 0x0f) : ((Slice_Twist_Prun[index >> 1] & 0xf0) >> 4)) == 0x0f)
{
setPruning(Slice_Twist_Prun, N_SLICE1 * newTwist + newSlice, (sbyte)(depth + 1));
done++;
}
}
}
}
depth++;
}
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Pruning table for the flip of the edges and the position (not permutation) of the UD-slice edges in phase1
// The pruning table entries give a lower estimation for the number of moves to reach the H-subgroup.
for (int i = 0; i < N_SLICE1 * N_FLIP / 2; i++)
{
Slice_Flip_Prun[i] = -1;
}
depth = 0;
setPruning(Slice_Flip_Prun, 0, 0);
done = 1;
while (done != N_SLICE1 * N_FLIP)
{
for (int i = 0; i < N_SLICE1 * N_FLIP; i++)
{
int flip = i / N_SLICE1, slice = i % N_SLICE1;
if (((i % 2 == 0) ? (Slice_Flip_Prun[i >> 1] & 0x0f) : ((Slice_Flip_Prun[i >> 1] & 0xf0) >> 4)) == depth)
{
for (int j = 0; j < 18; j++)
{
int newSlice = FRtoBR_Move[slice * 24, j] / 24;
int newFlip = flipMove[flip, j];
int index = N_SLICE1 * newFlip + newSlice;
if (((index % 2 == 0) ? (Slice_Flip_Prun[index >> 1] & 0x0f) : ((Slice_Flip_Prun[index >> 1] & 0xf0) >> 4)) == 0x0f)
{
setPruning(Slice_Flip_Prun, N_SLICE1 * newFlip + newSlice, (sbyte)(depth + 1));
done++;
}
}
}
}
depth++;
}
SavePrunData();
}