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diff --git a/kpat/freecell-solver/lookup2.c b/kpat/freecell-solver/lookup2.c
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+/*
+--------------------------------------------------------------------
+lookup2.c, by Bob Jenkins, December 1996, Public Domain.
+hash(), hash2(), hash3, and mix() are externally useful functions.
+Routines to test the hash are included if SELF_TEST is defined.
+You can use this free for any purpose.  It has no warranty.
+--------------------------------------------------------------------
+
+Note:
+    This code was ripped and modified by Shlomi Fish. The original can
+    be found at http://burtleburtle.net/bob/c/lookup2.c.
+*/
+
+#include <stdio.h>
+#include <stddef.h>
+#include <stdlib.h>
+
+#include "lookup2.h"
+
+
+#define hashsize(n) ((ub4)1<<(n))
+#define hashmask(n) (hashsize(n)-1)
+
+/*
+--------------------------------------------------------------------
+mix -- mix 3 32-bit values reversibly.
+For every delta with one or two bit set, and the deltas of all three
+  high bits or all three low bits, whether the original value of a,b,c
+  is almost all zero or is uniformly distributed,
+* If mix() is run forward or backward, at least 32 bits in a,b,c
+  have at least 1/4 probability of changing.
+* If mix() is run forward, every bit of c will change between 1/3 and
+  2/3 of the time.  (Well, 22/100 and 78/100 for some 2-bit deltas.)
+mix() was built out of 36 single-cycle latency instructions in a 
+  structure that could supported 2x parallelism, like so:
+      a -= b; 
+      a -= c; x = (c>>13);
+      b -= c; a ^= x;
+      b -= a; x = (a<<8);
+      c -= a; b ^= x;
+      c -= b; x = (b>>13);
+      ...
+  Unfortunately, superscalar Pentiums and Sparcs can't take advantage 
+  of that parallelism.  They've also turned some of those single-cycle
+  latency instructions into multi-cycle latency instructions.  Still,
+  this is the fastest good hash I could find.  There were about 2^^68
+  to choose from.  I only looked at a billion or so.
+--------------------------------------------------------------------
+*/
+#define mix(a,b,c) \
+{ \
+  a -= b; a -= c; a ^= (c>>13); \
+  b -= c; b -= a; b ^= (a<<8); \
+  c -= a; c -= b; c ^= (b>>13); \
+  a -= b; a -= c; a ^= (c>>12);  \
+  b -= c; b -= a; b ^= (a<<16); \
+  c -= a; c -= b; c ^= (b>>5); \
+  a -= b; a -= c; a ^= (c>>3);  \
+  b -= c; b -= a; b ^= (a<<10); \
+  c -= a; c -= b; c ^= (b>>15); \
+}
+
+/*
+--------------------------------------------------------------------
+ This works on all machines.  hash2() is identical to hash() on 
+ little-endian machines, except that the length has to be measured
+ in ub4s instead of bytes.  It is much faster than hash().  It 
+ requires
+ -- that the key be an array of ub4's, and
+ -- that all your machines have the same endianness, and
+ -- that the length be the number of ub4's in the key
+--------------------------------------------------------------------
+*/
+
+ub4 freecell_solver_lookup2_hash_function( 
+    register ub1 *k,        /* the key */
+    register ub4  length,   /* the length of the key */
+    register ub4  initval    /* the previous hash, or an arbitrary value */
+        )
+{
+   register ub4 a,b,c,len;
+
+   /* Set up the internal state */
+   len = length;
+   a = b = 0x9e3779b9;  /* the golden ratio; an arbitrary value */
+   c = initval;           /* the previous hash value */
+
+   /*---------------------------------------- handle most of the key */
+   while (len >= 12)
+   {
+      a += (k[0] +((ub4)k[1]<<8) +((ub4)k[2]<<16) +((ub4)k[3]<<24));
+      b += (k[4] +((ub4)k[5]<<8) +((ub4)k[6]<<16) +((ub4)k[7]<<24));
+      c += (k[8] +((ub4)k[9]<<8) +((ub4)k[10]<<16)+((ub4)k[11]<<24));
+      mix(a,b,c);
+      k += 12; len -= 12;
+   }
+
+   /*------------------------------------- handle the last 11 bytes */
+   c += length;
+   switch(len)              /* all the case statements fall through */
+   {
+   case 11: c+=((ub4)k[10]<<24);
+   case 10: c+=((ub4)k[9]<<16);
+   case 9 : c+=((ub4)k[8]<<8);
+      /* the first byte of c is reserved for the length */
+   case 8 : b+=((ub4)k[7]<<24);
+   case 7 : b+=((ub4)k[6]<<16);
+   case 6 : b+=((ub4)k[5]<<8);
+   case 5 : b+=k[4];
+   case 4 : a+=((ub4)k[3]<<24);
+   case 3 : a+=((ub4)k[2]<<16);
+   case 2 : a+=((ub4)k[1]<<8);
+   case 1 : a+=k[0];
+     /* case 0: nothing left to add */
+   }
+   mix(a,b,c);
+   /*-------------------------------------------- report the result */
+   return c;
+}