66 lines
1.1 KiB
C
66 lines
1.1 KiB
C
// quickSort
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//
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// This public-domain C implementation by Darel Rex Finley.
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//
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// Modified by Giuseppe Gatta
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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void qsort(void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *))
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{
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#define QSORT_MAX_LEVELS 300
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int beg[QSORT_MAX_LEVELS], end[QSORT_MAX_LEVELS], i=0, L, R, swap ;
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char piv[size];
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beg[0]=0; end[0]=nmemb;
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while (i>=0)
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{
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L=beg[i]; R=end[i]-1;
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if (L<R)
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{
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memcpy(piv, base + (size * L), size);
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while (L<R)
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{
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while(compar(base + (R*size), piv) > 0 && L<R) R--;
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if (L<R)
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{
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memcpy(base + (size *L), base + (size * R), size);
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L++;
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}
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while(compar(base + (L*size), piv) <= 0 && L<R) L++;
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if (L<R)
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{
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memcpy(base + (size *R), base + (size * L), size);
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R--;
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}
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}
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memcpy(base + (size*L), piv, size);
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beg[i+1]=L+1;
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end[i+1]=end[i];
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end[i++]=L;
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if (end[i]-beg[i]>end[i-1]-beg[i-1])
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{
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swap=beg[i]; beg[i]=beg[i-1]; beg[i-1]=swap;
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swap=end[i]; end[i]=end[i-1]; end[i-1]=swap;
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}
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}
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else
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{
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i--;
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}
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}
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}
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