#include "y1.h"

int
state( int c)
   {
   /* sorts last state,and sees if it equals earlier ones. returns state number */
   int size1,size2;
   register i;
   int *s;                                                              /*01*/
   struct looksets *ss;                                         /*01*/
   int s__;                                                     /*01*/
   struct item *p1, *p2, *k, *l, *q1, *q2;
   p1 = pstate[nstate];
   p2 = pstate[nstate+1];
   if(p1==p2) return(0); /* null state */
   /* sort the items */
   for(k=p2-1;k>p1;k--) 
      {
      /* make k the biggest */
      for(l=k-1;l>=p1;--l)if( l->pitem > k->pitem )
         {
         s = k->pitem;
         k->pitem = l->pitem;
         l->pitem = s;
         ss = k->look;
         k->look = l->look;
         l->look = ss;
         }
      }
   size1 = p2 - p1; /* size of state */

   for( i= (c>=NTBASE)?ntstates[c-NTBASE]:tstates[c]; i != 0; i = mstates[i] ) 
      {
      /* get ith state */
      q1 = pstate[i];
      q2 = pstate[i+1];
      size2 = q2 - q1;
      if (size1 != size2) continue;
      k=p1;
      for(l=q1;l<q2;l++) 
         {
         if( l->pitem != k->pitem ) break;
         ++k;
         }
      if (l != q2) continue;
      /* found it */
      pstate[nstate+1] = pstate[nstate]; /* delete last state */
      /* fix up lookaheads */
      if( nolook ) return(i);
      for( l=q1,k=p1; l<q2; ++l,++k )
         {
         SETLOOP(s__) clset.lset[s__] = l->look->lset[s__];
         if( setunion( clset.lset, k->look->lset ) ) 
            {
            tystate[i] = MUSTDO;
            /* register the new set */
            l->look = flset( &clset );
            }
         }
      return (i);
      }
   /* state is new */
   if( nolook ) error( "yacc state/nolook error" );
   pstate[nstate+2] = p2;
   if(nstate+1 >= NSTATES) error("too many states" );
   if( c >= NTBASE )
      {
      mstates[ nstate ] = ntstates[ c-NTBASE ];
      ntstates[ c-NTBASE ] = nstate;
      }
   else 
      {
      mstates[ nstate ] = tstates[ c ];
      tstates[ c ] = nstate;
      }
   tystate[nstate]=MUSTDO;
   return(nstate++);
   }