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myqsort.c 11.15 KiB
/*
* Copyright 1997, Regents of the University of Minnesota
*
* myqsort.c
*
* This file contains a fast idxtype increasing qsort algorithm.
* Addopted from TeX
*
* Started 10/18/96
* George
*
* $Id: myqsort.c,v 1.1 2005-09-07 14:36:45 remacle Exp $
*/
#include <metis.h> /* only for type declarations */
#define THRESH 1 /* threshold for insertion */
#define MTHRESH 6 /* threshold for median */
static void siqst(idxtype *, idxtype *);
static void iiqst(int *, int *);
static void keyiqst(KeyValueType *, KeyValueType *);
static void keyvaliqst(KeyValueType *, KeyValueType *);
/*************************************************************************
* Entry point of idxtype increasing sort
**************************************************************************/
void iidxsort(int n, idxtype *base)
{
register idxtype *i;
register idxtype *j;
register idxtype *lo;
register idxtype *hi;
register idxtype *min;
register idxtype c;
idxtype *max;
if (n <= 1)
return;
max = base + n;
if (n >= THRESH) {
siqst(base, max);
hi = base + THRESH;
}
else
hi = max;
for (j = lo = base; lo++ < hi;) {
if (*j > *lo)
j = lo;
}
if (j != base) { /* swap j into place */
c = *base;
*base = *j;
*j = c;
}
for (min = base; (hi = min += 1) < max;) {
while (*(--hi) > *min);
if ((hi += 1) != min) {
for (lo = min + 1; --lo >= min;) {
c = *lo;
for (i = j = lo; (j -= 1) >= hi; i = j)
*i = *j; *i = c;
}
}
}
}
static void siqst(idxtype *base, idxtype *max)
{
register idxtype *i;
register idxtype *j;
register idxtype *jj;
register idxtype *mid;
register int ii;
register idxtype c;
idxtype *tmp;
int lo;
int hi;
lo = max - base; /* number of elements as idxtype */
do {
mid = base + ((unsigned) lo>>1);
if (lo >= MTHRESH) {
j = (*base > *mid ? base : mid);
tmp = max - 1;
if (*j > *tmp) {
j = (j == base ? mid : base); /* switch to first loser */
if (*j < *tmp)
j = tmp;
}
if (j != mid) { /* SWAP */
c = *mid;
*mid = *j;
*j = c;
}
}
/* Semi-standard quicksort partitioning/swapping */
for (i = base, j = max - 1;;) {
while (i < mid && *i <= *mid)
i++;
while (j > mid) {
if (*mid <= *j) {
j--;
continue;
}
tmp = i + 1; /* value of i after swap */
if (i == mid) /* j <-> mid, new mid is j */
mid = jj = j;
else /* i <-> j */
jj = j--;
goto swap;
}
if (i == mid)
break;
else { /* i <-> mid, new mid is i */
jj = mid;
tmp = mid = i; /* value of i after swap */
j--;
}
swap:
c = *i;
*i = *jj;
*jj = c;
i = tmp;
}
i = (j = mid) + 1;
if ((lo = j - base) <= (hi = max - i)) { if (lo >= THRESH)
siqst(base, j);
base = i;
lo = hi;
}
else {
if (hi >= THRESH)
siqst(i, max);
max = j;
}
} while (lo >= THRESH);
}
/*************************************************************************
* Entry point of int increasing sort
**************************************************************************/
void iintsort(int n, int *base)
{
register int *i;
register int *j;
register int *lo;
register int *hi;
register int *min;
register int c;
int *max;
if (n <= 1)
return;
max = base + n;
if (n >= THRESH) {
iiqst(base, max);
hi = base + THRESH;
}
else
hi = max;
for (j = lo = base; lo++ < hi;) {
if (*j > *lo)
j = lo;
}
if (j != base) { /* swap j into place */
c = *base;
*base = *j;
*j = c;
}
for (min = base; (hi = min += 1) < max;) {
while (*(--hi) > *min);
if ((hi += 1) != min) {
for (lo = min + 1; --lo >= min;) {
c = *lo;
for (i = j = lo; (j -= 1) >= hi; i = j)
*i = *j;
*i = c;
}
}
}
}
static void iiqst(int *base, int *max)
{
register int *i;
register int *j; register int *jj;
register int *mid;
register int ii;
register int c;
int *tmp;
int lo;
int hi;
lo = max - base; /* number of elements as ints */
do {
mid = base + ((unsigned) lo>>1);
if (lo >= MTHRESH) {
j = (*base > *mid ? base : mid);
tmp = max - 1;
if (*j > *tmp) {
j = (j == base ? mid : base); /* switch to first loser */
if (*j < *tmp)
j = tmp;
}
if (j != mid) { /* SWAP */
c = *mid;
*mid = *j;
*j = c;
}
}
/* Semi-standard quicksort partitioning/swapping */
for (i = base, j = max - 1;;) {
while (i < mid && *i <= *mid)
i++;
while (j > mid) {
if (*mid <= *j) {
j--;
continue;
}
tmp = i + 1; /* value of i after swap */
if (i == mid) /* j <-> mid, new mid is j */
mid = jj = j;
else /* i <-> j */
jj = j--;
goto swap;
}
if (i == mid)
break;
else { /* i <-> mid, new mid is i */
jj = mid;
tmp = mid = i; /* value of i after swap */
j--;
}
swap:
c = *i;
*i = *jj;
*jj = c;
i = tmp;
}
i = (j = mid) + 1;
if ((lo = j - base) <= (hi = max - i)) {
if (lo >= THRESH)
iiqst(base, j);
base = i;
lo = hi;
}
else {
if (hi >= THRESH)
iiqst(i, max);
max = j;
} } while (lo >= THRESH);
}
/*************************************************************************
* Entry point of KeyVal increasing sort, ONLY key part
**************************************************************************/
void ikeysort(int n, KeyValueType *base)
{
register KeyValueType *i;
register KeyValueType *j;
register KeyValueType *lo;
register KeyValueType *hi;
register KeyValueType *min;
register KeyValueType c;
KeyValueType *max;
if (n <= 1)
return;
max = base + n;
if (n >= THRESH) {
keyiqst(base, max);
hi = base + THRESH;
}
else
hi = max;
for (j = lo = base; lo++ < hi;) {
if (j->key > lo->key)
j = lo;
}
if (j != base) { /* swap j into place */
c = *base;
*base = *j;
*j = c;
}
for (min = base; (hi = min += 1) < max;) {
while ((--hi)->key > min->key);
if ((hi += 1) != min) {
for (lo = min + 1; --lo >= min;) {
c = *lo;
for (i = j = lo; (j -= 1) >= hi; i = j)
*i = *j;
*i = c;
}
}
}
/* Sanity check */
{
int i;
for (i=0; i<n-1; i++)
if (base[i].key > base[i+1].key)
printf("Something went wrong!\n");
}
}
static void keyiqst(KeyValueType *base, KeyValueType *max)
{
register KeyValueType *i;
register KeyValueType *j;
register KeyValueType *jj;
register KeyValueType *mid; register KeyValueType c;
KeyValueType *tmp;
int lo;
int hi;
lo = (max - base)>>1; /* number of elements as KeyValueType */
do {
mid = base + ((unsigned) lo>>1);
if (lo >= MTHRESH) {
j = (base->key > mid->key ? base : mid);
tmp = max - 1;
if (j->key > tmp->key) {
j = (j == base ? mid : base); /* switch to first loser */
if (j->key < tmp->key)
j = tmp;
}
if (j != mid) { /* SWAP */
c = *mid;
*mid = *j;
*j = c;
}
}
/* Semi-standard quicksort partitioning/swapping */
for (i = base, j = max - 1;;) {
while (i < mid && i->key <= mid->key)
i++;
while (j > mid) {
if (mid->key <= j->key) {
j--;
continue;
}
tmp = i + 1; /* value of i after swap */
if (i == mid) /* j <-> mid, new mid is j */
mid = jj = j;
else /* i <-> j */
jj = j--;
goto swap;
}
if (i == mid)
break;
else { /* i <-> mid, new mid is i */
jj = mid;
tmp = mid = i; /* value of i after swap */
j--;
}
swap:
c = *i;
*i = *jj;
*jj = c;
i = tmp;
}
i = (j = mid) + 1;
if ((lo = (j - base)>>1) <= (hi = (max - i)>>1)) {
if (lo >= THRESH)
keyiqst(base, j);
base = i;
lo = hi;
}
else {
if (hi >= THRESH)
keyiqst(i, max);
max = j;
}
} while (lo >= THRESH);
}
/*************************************************************************
* Entry point of KeyVal increasing sort, BOTH key and val part
**************************************************************************/
void ikeyvalsort(int n, KeyValueType *base)
{
register KeyValueType *i;
register KeyValueType *j;
register KeyValueType *lo;
register KeyValueType *hi;
register KeyValueType *min;
register KeyValueType c;
KeyValueType *max;
if (n <= 1)
return;
max = base + n;
if (n >= THRESH) {
keyvaliqst(base, max);
hi = base + THRESH;
}
else
hi = max;
for (j = lo = base; lo++ < hi;) {
if ((j->key > lo->key) || (j->key == lo->key && j->val > lo->val))
j = lo;
}
if (j != base) { /* swap j into place */
c = *base;
*base = *j;
*j = c;
}
for (min = base; (hi = min += 1) < max;) {
while ((--hi)->key > min->key || (hi->key == min->key && hi->val > min->val));
if ((hi += 1) != min) {
for (lo = min + 1; --lo >= min;) {
c = *lo;
for (i = j = lo; (j -= 1) >= hi; i = j)
*i = *j;
*i = c;
}
}
}
}
static void keyvaliqst(KeyValueType *base, KeyValueType *max)
{
register KeyValueType *i;
register KeyValueType *j;
register KeyValueType *jj;
register KeyValueType *mid;
register KeyValueType c;
KeyValueType *tmp;
int lo;
int hi;
lo = (max - base)>>1; /* number of elements as KeyValueType */
do {
mid = base + ((unsigned) lo>>1);
if (lo >= MTHRESH) {
j = (base->key > mid->key || (base->key == mid->key && base->val > mid->val) ? base : mid);
tmp = max - 1;
if (j->key > tmp->key || (j->key == tmp->key && j->val > tmp->val)) { j = (j == base ? mid : base); /* switch to first loser */
if (j->key < tmp->key || (j->key == tmp->key && j->val < tmp->val))
j = tmp;
}
if (j != mid) { /* SWAP */
c = *mid;
*mid = *j;
*j = c;
}
}
/* Semi-standard quicksort partitioning/swapping */
for (i = base, j = max - 1;;) {
while (i < mid && (i->key < mid->key || (i->key == mid->key && i->val <= mid->val)))
i++;
while (j > mid) {
if (mid->key < j->key || (mid->key == j->key && mid->val <= j->val)) {
j--;
continue;
}
tmp = i + 1; /* value of i after swap */
if (i == mid) /* j <-> mid, new mid is j */
mid = jj = j;
else /* i <-> j */
jj = j--;
goto swap;
}
if (i == mid)
break;
else { /* i <-> mid, new mid is i */
jj = mid;
tmp = mid = i; /* value of i after swap */
j--;
}
swap:
c = *i;
*i = *jj;
*jj = c;
i = tmp;
}
i = (j = mid) + 1;
if ((lo = (j - base)>>1) <= (hi = (max - i)>>1)) {
if (lo >= THRESH)
keyvaliqst(base, j);
base = i;
lo = hi;
}
else {
if (hi >= THRESH)
keyvaliqst(i, max);
max = j;
}
} while (lo >= THRESH);
}