42 lines
966 B
C
42 lines
966 B
C
/*
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* bsearch - binary search!
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*
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* This header is a part of the FENIX C Library and is free software.
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* You can redistribute and/or modify it subject to the terms of the
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* Clumsy Wolf Public License v4. For more details, see the file COPYING.
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*
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* The FENIX C Library is distributed WITH NO WARRANTY WHATSOEVER. See
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* The CWPL for more details.
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*/
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#include <stdlib.h>
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void * bsearch(const void * key, const void * base, size_t nel, size_t width,
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int (*compar)(const void *, const void*)) {
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long int left;
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long int right;
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long int mid;
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if(nel == 0 || base == NULL) {
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return NULL;
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}
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left = (long int) base;
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right = (long int) (base + (nel * width));
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while(left <= right) {
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mid = (left + right) / 2;
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int t = compar(key, (void *) mid);
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if(t == 0) {
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return (void *) mid;
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}
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else if(t < 0) {
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right = mid - width;
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}
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else if(t > 0) {
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left = mid + width;
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}
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}
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return NULL;
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} |