quicksort.c
#include "quicksort.h"
int compare( byte *a , byte *b ) ;
void memswap( byte *s, byte *t, int count ) {
byte tmp ;
while (count-- > 0 ){
tmp = *s ;
*s++ = *t ;
*t++ = tmp ;
}
}
byte *select_pivot(byte data[], int n , int elementsize , int (*p_cmp_f)() ){
return data ;
}
void quicksort( byte data[], int n, int elementsize, int (*p_cmp_f)( ) ) {
byte *p_left , *p_right , *p_pivot ;
int leftsize ;
if(n <= 1 )
return ;
p_left = data ;
p_right = data + ( n-1) * elementsize ;
p_pivot = select_pivot(data,n,elementsize,p_cmp_f) ;
memswap(p_pivot,p_right,elementsize) ;
p_pivot = p_right ;
while(p_left < p_right){
while ((*p_cmp_f)(p_left,p_pivot) < 0 && p_left < p_right )
p_left += elementsize ;
while ((*p_cmp_f)(p_right,p_pivot) >= 0 && p_left < p_right )
p_right -= elementsize ;
if(p_left < p_right){
memswap(p_left,p_right,elementsize) ;
p_left += elementsize ;
}
}
if(p_right == data){
memswap(p_right,p_pivot,elementsize) ;
p_right += elementsize ;
}
leftsize = (p_right - data) / elementsize ;
quicksort(data,leftsize,elementsize,compare) ;
quicksort(p_right,n-leftsize,elementsize,p_cmp_f) ;
}main.c
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "quicksort.h"
#include "quicksort.c"
int compare( byte *a , byte *b ) {
if(*(int *)a < *(int *)b ) return -1 ;
if(*(int *)a == *(int *)b ) return 0 ;
return 1 ;
}
int main( int argc, char *argv[] ) {
double *A ;
int n , i ;
time_t start ;
time_t stop ;
n = atoi( argv[1] ) ;
A = ( double *) malloc(sizeof(double)*n) ;
if ( A == NULL ){ printf(" Error mallocing \n" ); return -1 ; }
for ( i = 0 ; i <= n ; i++ ) A[i] = rand() % 10000 ;
for ( i = 0 ; i <= 19 ; i++ ) printf(" %.2f ", A[i] ) ;
printf("\n") ;
start = time( NULL ) ;
quicksort( (byte *) A, n , sizeof(double) , compare ) ;
stop = time( NULL ) ;
printf("\n") ;
for ( i = 0 ; i <= 19 ; i++ ) printf(" %.2f ", A[i] ) ;
printf("\n") ;
printf("\nTime: %d seconds\n", (int)difftime( stop, start ) ) ;
return 0 ;
}quicksort.h
#ifndef _header
#define _header
typedef char byte ;
extern void quicksort(byte data[], int n , int elementsize , int (*p_cmp_f)() ) ;
#endifbuilt a quicksort.o file with the quicksort.c
and then compiled it like this gcc -ansi -Wall -o quicksort main.c quicksort.o
errors i get:
quicksort.o: In function `memswap':
quicksort.c:(.text+0x0): multiple definition of `memswap'
/tmp/ccwpEZSE.o:main1.c:(.text+0x0): first defined here
quicksort.o: In function `select_pivot':
quicksort.c:(.text+0x3e): multiple definition of `select_pivot'
/tmp/ccwpEZSE.o:main1.c:(.text+0x3e): first defined here
quicksort.o: In function `quicksort':
quicksort.c:(.text+0x46): multiple definition of `quicksort'
/tmp/ccwpEZSE.o:main1.c:(.text+0x46): first defined here
collect2: ld returned 1 exit status