关于实现魔方复原的Thistlethwaite Algorithm

几天把关于用Thistlethwaite Algorithm实现3X3X3阶的算法用java实现了。

因为太复杂了，就采用了别人已经写好的算法给转换了一下。参考网站：

http://www.diy-robots.com/?p=282import java.util.Scanner ;public class cube{public static void main(String[] args){Scanner inScanner = new Scanner(System.in) ;while (inScanner.hasNextLine()){String str = inScanner.nextLine() ;System.out.println(GetResult(str)) ;}}public static String GetResult(String sInput){phase = 0 ;String[] argv = sInput.split(" ") ;String sOutput = "" ;if (argv.length != 20){return "error" ;}int f , i = 0 , j = 0 , k = 0 , pc , mor ;for ( ; k < 20 ; k ++ ){tmpStr = Character.toChars(k < 12 ? 2 : 3) ;val[k] = tmpStr[0] ;}for ( ; j < 8 ; j ++ )filltable(j) ;for ( ; i < 20 ; i ++ ){f = pc = k = mor = 0 ;for ( ; f < val[i] ; f ++ ){j = faces.indexOf(argv[i].charAt(f)) ;if (j > k){k = j ;mor = f ;}pc += 1 << j ;}for (f = 0 ; f < 20 ; f ++ )if (pc == bithash[f] - 64)break ;tmpStr = Character.toChars(f) ;pos[order[i] - CHAROFFSET] = tmpStr[0] ;tmpStr = Character.toChars(mor % val[i]) ;ori[order[i] - CHAROFFSET] = tmpStr[0] ;}for ( ; phase < 8 ; phase += 2){for (j = 0 ; ! searchphase(j , 0 , 9) ; j ++ );for (i = 0 ; i < j ; i ++ ){sOutput += "FBRLUD".charAt(move[i]) + "" + moveamount[i] ;sOutput += " " ;}}return sOutput ;}public static int Char2Num(char c){return (int) c - CHAROFFSET ;}public static void cycle(char[] p , char[] a , int offset){char temp = p[Char2Num(a[0 + offset])] ;p[Char2Num(a[0 + offset])] = p[Char2Num(a[1 + offset])] ;p[Char2Num(a[1 + offset])] = temp ;temp = p[Char2Num(a[0 + offset])] ;p[Char2Num(a[0 + offset])] = p[Char2Num(a[2 + offset])] ;p[Char2Num(a[2 + offset])] = temp ;temp = p[Char2Num(a[0 + offset])] ;p[Char2Num(a[0 + offset])] = p[Char2Num(a[3 + offset])] ;p[Char2Num(a[3 + offset])] = temp ;}public static void twist(int i , int a){i -= CHAROFFSET ;tmpStr = Character.toChars(((int) ori[i] + a + 1) % val[i]) ;ori[i] = tmpStr[0] ;}public static void reset(){for (int i = 0 ; i < 20 ;){tmpStr = Character.toChars(i) ;pos[i] = tmpStr[0] ;ori[i ++ ] = '/0' ;}}public static int permtonum(char[] p , int offset){int n = 0 ;for (int a = 0 ; a < 4 ; a ++ ){n *= 4 - a ;for (int b = a ; ++ b < 4 ;)if (p[b + offset] < p[a + offset])n ++ ;}return n ;}public static void numtoperm(char[] p , int n , int o){tmpStr = Character.toChars(o) ;p[3 + o] = tmpStr[0] ;for (int a = 3 ; a -- > 0 ;){tmpStr = Character.toChars(n % (4 - a) + o) ;p[a + o] = tmpStr[0] ;n /= 4 - a ;for (int b = a ; ++ b < 4 ;)if (p[b + o] >= p[a + o])p[b + o] ++ ;}}public static int getposition(int t){int i = - 1 , n = 0 ;switch (t){case 1 :for ( ; ++ i < 12 ;)n += ((int) ori[i]) << i ;break ;case 2 :for (i = 20 ; -- i > 11 ;)n = n * 3 + (int) ori[i] ;break ;case 3 :for ( ; ++ i < 12 ;)n += ((((int) pos[i]) & 8) > 0) ? (1 << i) : 0 ;break ;case 4 :for ( ; ++ i < 8 ;)n += ((((int) pos[i]) & 4) > 0) ? (1 << i) : 0 ;break ;case 5 :int[] corn = new int[8] ;int[] corn2 = new int[4] ;int j ,k ,l ;k = j = 0 ;for ( ; ++ i < 8 ;)if (((l = pos[i + 12] - 12) & 4) > 0){corn[l] = k ++ ;n += 1 << i ;}elsecorn[j ++ ] = l ;for (i = 0 ; i < 4 ; i ++ )corn2[i] = corn[4 + corn[i]] ;for ( ; -- i > 0 ;)corn2[i] ^= corn2[0] ;n = n * 6 + corn2[1] * 2 - 2 ;if (corn2[3] < corn2[2])n ++ ;break ;case 6 :n = permtonum(pos , 0) * 576 + permtonum(pos , 4) * 24 + permtonum(pos , 12) ;break ;case 7 :n = permtonum(pos , 8) * 24 + permtonum(pos , 16) ;break ;}return n ;}public static void setposition(int t , int n){int i = 0 , j = 12 , k = 0 ;char[] corn = "QRSTQRTSQSRTQTRSQSTRQTSR".toCharArray() ;reset() ;switch (t){case 1 :for ( ; i < 12 ; i ++ , n >>= 1){tmpStr = Character.toChars(n & 1) ;ori[i] = tmpStr[0] ;}break ;case 2 :for (i = 12 ; i < 20 ; i ++ , n /= 3){tmpStr = Character.toChars(n % 3) ;ori[i] = tmpStr[0] ;}break ;case 3 :for ( ; i < 12 ; i ++ , n >>= 1){tmpStr = Character.toChars(8 * n & 8) ;pos[i] = tmpStr[0] ;}break ;case 4 :for ( ; i < 8 ; i ++ , n >>= 1){tmpStr = Character.toChars(4 * n & 4) ;pos[i] = tmpStr[0] ;}break ;case 5 :int offset = n % 6 * 4 ;n /= 6 ;for ( ; i < 8 ; i ++ , n >>= 1){tmpStr = Character.toChars(((n & 1) > 0) ? corn[offset + k ++ ] - CHAROFFSET : j ++ ) ;pos[i + 12] = tmpStr[0] ;}break ;case 6 :numtoperm(pos , n % 24 , 12) ;n /= 24 ;numtoperm(pos , n % 24 , 4) ;n /= 24 ;numtoperm(pos , n , 0) ;break ;case 7 :numtoperm(pos , n / 24 , 8) ;numtoperm(pos , n % 24 , 16) ;break ;}}public static void domove(int m){int offset = 8 * m ;int i = 8 ;cycle(pos , perm , offset) ;cycle(ori , perm , offset) ;cycle(pos , perm , offset + 4) ;cycle(ori , perm , offset + 4) ;if (m < 4)for ( ; -- i > 3 ;)twist(perm[i + offset] , i & 1) ;if (m < 2)for (i = 4 ; i -- > 0 ;)twist(perm[i + offset] , 0) ;}public static void filltable(int ti){int n = 1 , l = 1 , tl = tablesize[ti] ;char[] tb = new char[tl] ;tables[ti] = tb ;for (int i = 0 ; i < tb.length ; i ++ )tb[i] = '/0' ;reset() ;tmpStr = Character.toChars(1) ;tb[getposition(ti)] = tmpStr[0] ;while (n > 0){n = 0 ;for (int i = 0 ; i < tl ; i ++ ){if (tb[i] == l){setposition(ti , i) ;for (int f = 0 ; f < 6 ; f ++ ){for (int q = 1 ; q < 4 ; q ++ ){domove(f) ;int r = getposition(ti) ;if ((q == 2 || f >= (ti & 6)) && tb[r] == '/0'){tmpStr = Character.toChars(l + 1) ;tb[r] = tmpStr[0] ;n ++ ;}}domove(f) ;}}}l ++ ;}}public static boolean searchphase(int movesleft , int movesdone , int lastmove){if (tables[phase][getposition(phase)] - 1 > movesleft || tables[phase + 1][getposition(phase + 1)] - 1 > movesleft)return false ;if (movesleft == 0)return true ;for (int i = 6 ; i -- > 0 ;){if ((i - lastmove != 0) && ((i - lastmove + 1) != 0 || ((i | 1) != 0))){move[movesdone] = i ;for (int j = 0 ; ++ j < 4 ;){domove(i) ;moveamount[movesdone] = j ;if ((j == 2 || i >= phase) && searchphase(movesleft - 1 , movesdone + 1 , i))return true ;}domove(i) ;}}return false ;}private static String faces = "RLFBUD" ;private static char[] order = "AECGBFDHIJKLMSNTROQP".toCharArray() ;private static char[] bithash = "TdXhQaRbEFIJUZfijeYV".toCharArray() ;private static char[] perm = "AIBJTMROCLDKSNQPEKFIMSPRGJHLNTOQAGCEMTNSBFDHORPQ" .toCharArray() ;private static char[] pos = new char[20] ;private static char[] ori = new char[20] ;private static char[] val = new char[20] ;private static char[][] tables = new char[8][] ;private static int[] move = new int[20] ;private static int[] moveamount = new int[20] ;private static int phase = 0 ;private static int[] tablesize ={ 1 , 4096 , 6561 , 4096 , 256 , 1536 , 13824 , 576 } ;private static int CHAROFFSET = 65 ;private static char[] tmpStr = new char[20] ;}