// This may look like C code, but it is really -*- C++ -*-/* Copyright (C) 1988 Free Software Foundation    written by Doug Lea (dl@rocky.oswego.edu)This file is part of the GNU C++ Library.  This library is freesoftware; you can redistribute it and/or modify it under the terms ofthe GNU Library General Public License as published by the FreeSoftware Foundation; either version 2 of the License, or (at youroption) any later version.  This library is distributed in the hopethat it will be useful, but WITHOUT ANY WARRANTY; without even theimplied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULARPURPOSE.  See the GNU Library General Public License for more details.You should have received a copy of the GNU Library General PublicLicense along with this library; if not, write to the Free SoftwareFoundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.*/#ifdef __GNUG__#pragma implementation#endif// #include <stream.h>#include <stdlib.h>#include "lib/builtin.h"#include "lib/int.Vec.h"// error handlingvoid default_intVec_error_handler(const char* msg){#if 0  cerr << "Fatal intVec error. " << msg << "\n";#else  // ns doesn't use streams  fprintf(stderr, "Fatal intVec error. %s\n", msg);#endif  exit(1);}one_arg_error_handler_t intVec_error_handler = default_intVec_error_handler;one_arg_error_handler_t set_intVec_error_handler(one_arg_error_handler_t f){  one_arg_error_handler_t old = intVec_error_handler;  intVec_error_handler = f;  return old;}void intVec::error(const char* msg){  (*intVec_error_handler)(msg);}void intVec::range_error(){  (*intVec_error_handler)("Index out of range.");}intVec::intVec(const intVec& v){  s = new int [len = v.len];  int* top = &(s[len]);  int* t = s;  const int* u = v.s;  while (t < top) *t++ = *u++;}intVec::intVec(int l, int  fill_value){  s = new int [len = l];  int* top = &(s[len]);  int* t = s;  while (t < top) *t++ = fill_value;}intVec& intVec::operator = (const intVec& v){  if (this != &v)  {    delete [] s;    s = new int [len = v.len];    int* top = &(s[len]);    int* t = s;    const int* u = v.s;    while (t < top) *t++ = *u++;  }  return *this;}void intVec::apply(intProcedure f){  int* top = &(s[len]);  int* t = s;  while (t < top) (*f)(*t++);}// can't just realloc since there may be need for constructors/destructorsvoid intVec::resize(int newl){  int* news = new int [newl];  int* p = news;  int minl = (len < newl)? len : newl;  int* top = &(s[minl]);  int* t = s;  while (t < top) *p++ = *t++;  delete [] s;  s = news;  len = newl;}intVec concat(intVec & a, intVec & b){  int newl = a.len + b.len;  int* news = new int [newl];  int* p = news;  int* top = &(a.s[a.len]);  int* t = a.s;  while (t < top) *p++ = *t++;  top = &(b.s[b.len]);  t = b.s;  while (t < top) *p++ = *t++;  return intVec(newl, news);}intVec combine(intCombiner f, intVec& a, intVec& b){  int newl = (a.len < b.len)? a.len : b.len;  int* news = new int [newl];  int* p = news;  int* top = &(a.s[newl]);  int* t = a.s;  int* u = b.s;  while (t < top) *p++ = (*f)(*t++, *u++);  return intVec(newl, news);}int intVec::reduce(intCombiner f, int  base){  int r = base;  int* top = &(s[len]);  int* t = s;  while (t < top) r = (*f)(r, *t++);  return r;}intVec reverse(intVec& a){  int* news = new int [a.len];  if (a.len != 0)  {    int* lo = news;    int* hi = &(news[a.len - 1]);    while (lo < hi)    {      int tmp = *lo;      *lo++ = *hi;      *hi-- = tmp;    }  }  return intVec(a.len, news);}void intVec::reverse(){  if (len != 0)  {    int* lo = s;    int* hi = &(s[len - 1]);    while (lo < hi)    {      int tmp = *lo;      *lo++ = *hi;      *hi-- = tmp;    }  }}int intVec::index(int  targ){  for (int i = 0; i < len; ++i) if (intEQ(targ, s[i])) return i;  return -1;}intVec map(intMapper f, intVec& a){  int* news = new int [a.len];  int* p = news;  int* top = &(a.s[a.len]);  int* t = a.s;  while(t < top) *p++ = (*f)(*t++);  return intVec(a.len, news);}int operator == (intVec& a, intVec& b){  if (a.len != b.len)    return 0;  int* top = &(a.s[a.len]);  int* t = a.s;  int* u = b.s;  while (t < top) if (!(intEQ(*t++, *u++))) return 0;  return 1;}void intVec::fill(int  val, int from, int n){  int to;  if (n < 0)    to = len - 1;  else    to = from + n - 1;  if ((unsigned)from > (unsigned)to)    range_error();  int* t = &(s[from]);  int* top = &(s[to]);  while (t <= top) *t++ = val;}intVec intVec::at(int from, int n){  int to;  if (n < 0)  {    n = len - from;    to = len - 1;  }  else    to = from + n - 1;  if ((unsigned)from > (unsigned)to)    range_error();  int* news = new int [n];  int* p = news;  int* t = &(s[from]);  int* top = &(s[to]);  while (t <= top) *p++ = *t++;  return intVec(n, news);}intVec merge(intVec & a, intVec & b, intComparator f){  int newl = a.len + b.len;  int* news = new int [newl];  int* p = news;  int* topa = &(a.s[a.len]);  int* as = a.s;  int* topb = &(b.s[b.len]);  int* bs = b.s;  for (;;)  {    if (as >= topa)    {      while (bs < topb) *p++ = *bs++;      break;    }    else if (bs >= topb)    {      while (as < topa) *p++ = *as++;      break;    }    else if ((*f)(*as, *bs) <= 0)      *p++ = *as++;    else      *p++ = *bs++;  }  return intVec(newl, news);}static int gsort(int*, int, intComparator); void intVec::sort (intComparator compar){  gsort(s, len, compar);}// An adaptation of Schmidt's new quicksortstatic inline void SWAP(int* A, int* B){  int tmp = *A; *A = *B; *B = tmp;}/* This should be replaced by a standard ANSI macro. */#define BYTES_PER_WORD 8#define BYTES_PER_LONG 4/* The next 4 #defines implement a very fast in-line stack abstraction. */#define STACK_SIZE (BYTES_PER_WORD * BYTES_PER_LONG)#define PUSH(LOW,HIGH) do {top->lo = LOW;top++->hi = HIGH;} while (0)#define POP(LOW,HIGH)  do {LOW = (--top)->lo;HIGH = top->hi;} while (0)#define STACK_NOT_EMPTY (stack < top)                /* Discontinue quicksort algorithm when partition gets below this size.   This particular magic number was chosen to work best on a Sun 4/260. */#define MAX_THRESH 4/* Order size using quicksort.  This implementation incorporates   four optimizations discussed in Sedgewick:      1. Non-recursive, using an explicit stack of pointer that      store the next array partition to sort.  To save time, this      maximum amount of space required to store an array of      MAX_INT is allocated on the stack.  Assuming a 32-bit integer,      this needs only 32 * sizeof (stack_node) == 136 bits.  Pretty      cheap, actually.   2. Chose the pivot element using a median-of-three decision tree.      This reduces the probability of selecting a bad pivot value and       eliminates certain extraneous comparisons.   3. Only quicksorts TOTAL_ELEMS / MAX_THRESH partitions, leaving      insertion sort to order the MAX_THRESH items within each partition.        This is a big win, since insertion sort is faster for small, mostly      sorted array segements.      4. The larger of the two sub-partitions is always pushed onto the      stack first, with the algorithm then concentrating on the      smaller partition.  This *guarantees* no more than log (n)      stack size is needed! */      static int gsort (int *base_ptr, int total_elems, intComparator cmp){/* Stack node declarations used to store unfulfilled partition obligations. */  struct stack_node {  int *lo;  int *hi; };  int   pivot_buffer;  int   max_thresh   = MAX_THRESH;  if (total_elems > MAX_THRESH)    {      int       *lo = base_ptr;      int       *hi = lo + (total_elems - 1);      int       *left_ptr;      int       *right_ptr;      stack_node stack[STACK_SIZE]; /* Largest size needed for 32-bit int!!! */      stack_node *top = stack + 1;      while (STACK_NOT_EMPTY)        {          {            int *pivot = &pivot_buffer;            {              /* Select median value from among LO, MID, and HI. Rearrange                 LO and HI so the three values are sorted. This lowers the                  probability of picking a pathological pivot value and                  skips a comparison for both the LEFT_PTR and RIGHT_PTR. */              int *mid = lo + ((hi - lo) >> 1);              if ((*cmp) (*mid, *lo) < 0)                SWAP (mid, lo);              if ((*cmp) (*hi, *mid) < 0)              {                SWAP (mid, hi);                if ((*cmp) (*mid, *lo) < 0)                  SWAP (mid, lo);              }              *pivot = *mid;              pivot = &pivot_buffer;            }            left_ptr  = lo + 1;            right_ptr = hi - 1;             /* Here's the famous ``collapse the walls'' section of quicksort.                 Gotta like those tight inner loops!  They are the main reason                that this algorithm runs much faster than others. */            do               {                while ((*cmp) (*left_ptr, *pivot) < 0)                  left_ptr += 1;                while ((*cmp) (*pivot, *right_ptr) < 0)                  right_ptr -= 1;                if (left_ptr < right_ptr)                   {                    SWAP (left_ptr, right_ptr);                    left_ptr += 1;                    right_ptr -= 1;                  }                else if (left_ptr == right_ptr)                   {                    left_ptr += 1;                    right_ptr -= 1;                    break;                  }              }             while (left_ptr <= right_ptr);          }          /* Set up pointers for next iteration.  First determine whether             left and right partitions are below the threshold size. If so,              ignore one or both.  Otherwise, push the larger partition's             bounds on the stack and continue sorting the smaller one. */          if ((right_ptr - lo) <= max_thresh)            {              if ((hi - left_ptr) <= max_thresh) /* Ignore both small partitions. */                POP (lo, hi);               else              /* Ignore small left partition. */                  lo = left_ptr;            }          else if ((hi - left_ptr) <= max_thresh) /* Ignore small right partition. */            hi = right_ptr;          else if ((right_ptr - lo) > (hi - left_ptr)) /* Push larger left partition indices. */            {                                 PUSH (lo, right_ptr);              lo = left_ptr;            }          else                  /* Push larger right partition indices. */            {                                 PUSH (left_ptr, hi);              hi = right_ptr;            }        }    }  /* Once the BASE_PTR array is partially sorted by quicksort the rest     is completely sorted using insertion sort, since this is efficient      for partitions below MAX_THRESH size. BASE_PTR points to the beginning      of the array to sort, and END_PTR points at the very last element in     the array (*not* one beyond it!). */  {    int *end_ptr = base_ptr + 1 * (total_elems - 1);    int *run_ptr;    int *tmp_ptr = base_ptr;    int *thresh  = (end_ptr < (base_ptr + max_thresh))?       end_ptr : (base_ptr + max_thresh);    /* Find smallest element in first threshold and place it at the       array's beginning.  This is the smallest array element,       and the operation speeds up insertion sort's inner loop. */    for (run_ptr = tmp_ptr + 1; run_ptr <= thresh; run_ptr += 1)      if ((*cmp) (*run_ptr, *tmp_ptr) < 0)        tmp_ptr = run_ptr;    if (tmp_ptr != base_ptr)      SWAP (tmp_ptr, base_ptr);    /* Insertion sort, running from left-hand-side up to `right-hand-side.'        Pretty much straight out of the original GNU qsort routine. */    for (run_ptr = base_ptr + 1; (tmp_ptr = run_ptr += 1) <= end_ptr; )      {        while ((*cmp) (*run_ptr, *(tmp_ptr -= 1)) < 0)          ;        if ((tmp_ptr += 1) != run_ptr)          {            int *trav;            for (trav = run_ptr + 1; --trav >= run_ptr;)              {                int c = *trav;                int *hi, *lo;                for (hi = lo = trav; (lo -= 1) >= tmp_ptr; hi = lo)                  *hi = *lo;                *hi = c;              }          }      }  }  return 1;}