31 lines
562 B
C
31 lines
562 B
C
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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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void * left;
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void * right;
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void * 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 = base;
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right = 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, mid);
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if(t == 0) {
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return 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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}
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