/*
 * This code is from "Algorithms in C, Third Edition,"
 * by Robert Sedgewick, Addison Wesley Longman, 1998.
 */
link split(link h)
  { int j; link t = NEW();
    for (j = 0; j < M/2; j++)
      t->b[j] = h->b[M/2+j]; 
    h->m = M/2; t->m = M/2; 
    return t;    
  }