C/sorting/multikey_quick_sort.c at master · SelfCodeLearning/C · GitHub

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/* demo.c -- Implementations of multikey quicksort and ternary search trees

Usage

demo Run basic timings on /usr/dict/words

demo <file> Run basic timings on <file>

demo <file> trysearch Interactive pm and nn search on <file>

demo <file> nncost Run near neigbhor expers on <file>

demo <file> pmcost Interactive partial match expers on <file>

#include <stdlib.h>

#include <string.h>

#include <stdio.h>

#include <time.h>

// MULTIKEY QUICKSORT

#ifndef min

#define min(a, b) ((a) <= (b) ? (a) : (b))

#endif

#define swap(a, b) \

{ \

char *t = x[a]; \

x[a] = x[b]; \

x[b] = t; \

}

#define i2c(i) x[i][depth]

void vecswap(int i, int j, int n, char *x[])

{

while (n-- > 0)

{

swap(i, j);

i++;

j++;

}

void ssort1(char *x[], int n, int depth)

{

int a, b, c, d, r, v;

if (n <= 1)

return;

a = rand() % n;

swap(0, a);

v = i2c(0);

a = b = 1;

c = d = n - 1;

for (;;)

{

while (b <= c && (r = i2c(b) - v) <= 0)

{

if (r == 0)

{

swap(a, b);

a++;

}

b++;

}

while (b <= c && (r = i2c(c) - v) >= 0)

{

if (r == 0)

{

swap(c, d);

d--;

}

c--;

}

if (b > c)

break;

swap(b, c);

b++;

c--;

}

r = min(a, b - a);

vecswap(0, b - r, r, x);

r = min(d - c, n - d - 1);

vecswap(b, n - r, r, x);

r = b - a;

ssort1(x, r, depth);

if (i2c(r) != 0)

ssort1(x + r, a + n - d - 1, depth + 1);

r = d - c;

ssort1(x + n - r, r, depth);

}

void ssort1main(char *x[], int n)

{

ssort1(x, n, 0);

}

// ssort2 -- Faster Version of Multikey Quicksort

void vecswap2(char **a, char **b, int n)

{

while (n-- > 0)

{

char *t = *a;

*a++ = *b;

*b++ = t;

}

#define swap2(a, b) \

{ \

t = *(a); \

*(a) = *(b); \

*(b) = t; \

}

#define ptr2char(i) (*(*(i) + depth))

char **med3func(char **a, char **b, char **c, int depth)

{

int va, vb, vc;

if ((va = ptr2char(a)) == (vb = ptr2char(b)))

return a;

if ((vc = ptr2char(c)) == va || vc == vb)

return c;

return va < vb ? (vb < vc ? b : (va < vc ? c : a))

: (vb > vc ? b : (va < vc ? a : c));

}

#define med3(a, b, c) med3func(a, b, c, depth)

void inssort(char **a, int n, int d)

{

char **pi, **pj, *s, *t;

for (pi = a + 1; --n > 0; pi++)

for (pj = pi; pj > a; pj--)

{

// Inline strcmp: break if *(pj-1) <= *pj

for (s = *(pj - 1) + d, t = *pj + d; *s == *t && *s != 0; s++, t++)

;

if (*s <= *t)

break;

swap2(pj, pj - 1);

}

void ssort2(char **a, int n, int depth)

{

int d, r, partval;

char **pa, **pb, **pc, **pd, **pl, **pm, **pn, *t;

if (n < 10)

{

inssort(a, n, depth);

return;

}

pl = a;

pm = a + (n / 2);

pn = a + (n - 1);

if (n > 30)

{ // On big arrays, pseudomedian of 9

d = (n / 8);

pl = med3(pl, pl + d, pl + 2 * d);

pm = med3(pm - d, pm, pm + d);

pn = med3(pn - 2 * d, pn - d, pn);

}

pm = med3(pl, pm, pn);

swap2(a, pm);

partval = ptr2char(a);

pa = pb = a + 1;

pc = pd = a + n - 1;

for (;;)

{

while (pb <= pc && (r = ptr2char(pb) - partval) <= 0)

{

if (r == 0)

{

swap2(pa, pb);

pa++;

}

pb++;

}

while (pb <= pc && (r = ptr2char(pc) - partval) >= 0)

{

if (r == 0)

{

swap2(pc, pd);

pd--;

}

pc--;

}

if (pb > pc)

break;

swap2(pb, pc);

pb++;

pc--;

}

pn = a + n;

r = min(pa - a, pb - pa);

vecswap2(a, pb - r, r);

r = min(pd - pc, pn - pd - 1);

vecswap2(pb, pn - r, r);

if ((r = pb - pa) > 1)

ssort2(a, r, depth);

if (ptr2char(a + r) != 0)

ssort2(a + r, pa - a + pn - pd - 1, depth + 1);

if ((r = pd - pc) > 1)

ssort2(a + n - r, r, depth);

}

void ssort2main(char **a, int n) { ssort2(a, n, 0); }

// TERNARY SEARCH TREE ALGS

typedef struct tnode *Tptr;

typedef struct tnode

{

char splitchar;

Tptr lokid, eqkid, hikid;

} Tnode;

Tptr root;

// Insert 1 -- Simple Insertion Algorithm

Tptr insert1(Tptr p, char *s)

{

if (p == 0)

{

p = (Tptr)malloc(sizeof(Tnode));

p->splitchar = *s;

p->lokid = p->eqkid = p->hikid = 0;

}

if (*s < p->splitchar)

p->lokid = insert1(p->lokid, s);

else if (*s == p->splitchar)

{

if (*s != 0)

p->eqkid = insert1(p->eqkid, ++s);

}

else

p->hikid = insert1(p->hikid, s);

return p;

}

void cleanup1(Tptr p)

{

if (p)

{

cleanup1(p->lokid);

cleanup1(p->eqkid);

cleanup1(p->hikid);

free(p);

}

// Insert 2 -- Faster version of Insert

#define BUFSIZE 1000

Tptr buf;

int bufn, freen;

void *freearr[10000];

int storestring = 0;

void insert2(char *s)

{

int d;

char *instr = s;

Tptr pp, *p;

p = &root;

while (pp = *p)

{

if ((d = *s - pp->splitchar) == 0)

{

if (*s++ == 0)

return;

p = &(pp->eqkid);

}

else if (d < 0)

p = &(pp->lokid);

else

p = &(pp->hikid);

}

for (;;)

{

// *p = (Tptr) malloc(sizeof(Tnode));

if (bufn-- == 0)

{

buf = (Tptr)malloc(BUFSIZE *

sizeof(Tnode));

freearr[freen++] = (void *)buf;

bufn = BUFSIZE - 1;

}

*p = buf++;

pp = *p;

pp->splitchar = *s;

pp->lokid = pp->eqkid = pp->hikid = 0;

if (*s++ == 0)

{

if (storestring)

pp->eqkid = (Tptr)instr;

return;

}

p = &(pp->eqkid);

}

void cleanup2()

{

int i;

for (i = 0; i < freen; i++)

free(freearr[i]);

}

// Search Algorithms

int search1(char *s)

{

Tptr p;

p = root;

while (p)

{

if (*s < p->splitchar)

p = p->lokid;

else if (*s == p->splitchar)

{

if (*s++ == 0)

return 1;

p = p->eqkid;

}

else

p = p->hikid;

}

return 0;

}

int search2(char *s)

{

int d, sc;

Tptr p;

sc = *s;

p = root;

while (p)

{

if ((d = sc - p->splitchar) == 0)

{

if (sc == 0)

return 1;

sc = *++s;

p = p->eqkid;

}

else if (d < 0)

p = p->lokid;

else

p = p->hikid;

}

return 0;

}

// Advanced searching: Partial match, near words

int nodecnt;

char *srcharr[100000];

int srchtop;

void pmsearch(Tptr p, char *s)

{

if (!p)

return;

nodecnt++;

if (*s == '.' || *s < p->splitchar)

pmsearch(p->lokid, s);

if (*s == '.' || *s == p->splitchar)

if (p->splitchar && *s)

pmsearch(p->eqkid, s + 1);

if (*s == 0 && p->splitchar == 0)

srcharr[srchtop++] =

(char *)p->eqkid;

if (*s == '.' || *s > p->splitchar)

pmsearch(p->hikid, s);

}

void nearsearch(Tptr p, char *s, int d)

{

if (!p || d < 0)

return;

nodecnt++;

if (d > 0 || *s < p->splitchar)

nearsearch(p->lokid, s, d);

if (p->splitchar == 0)

{

if ((int)strlen(s) <= d)

srcharr[srchtop++] =

(char *)p->eqkid;

}

else

nearsearch(p->eqkid, *s ? s + 1 : s,

(*s == p->splitchar) ? d : d - 1);

if (d > 0 || *s > p->splitchar)

nearsearch(p->hikid, s, d);

}

#define NUMBER_OF_STRING 3

int main(int argc, char *argv[])

{

char *arr[NUMBER_OF_STRING] = {"apple", "cat", "boy"};

ssort1main(arr, NUMBER_OF_STRING);

for (int i = 0; i < NUMBER_OF_STRING; i++)

{

printf("%s ", arr[i]);

}

C/sorting/multikey_quick_sort.c at master · SelfCodeLearning/C · GitHub

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