bsearch

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Version: 2003-11-01 (openSuse - 09/10/07)

Section: 3 (Bibliothèques de fonctions)

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bsearch - ¥½¡¼¥È¤µ¤ì¤¿ÇÛÎó¤òÆóʬÌÚ¸¡º÷ (binary search) ¤¹¤ë

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#include <stdlib.h>



void *bsearch(const void *key, const void *base, size_t nmemb,
size_t size, int (*compar)(const void *, const void *));

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SVr4, 4.3BSD, POSIX.1-2001, C89, C99

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#include <stdio.h>

#include <stdlib.h>

#include <string.h>



struct mi {

    int nr;

    char *name;

} months[] = {

    { 1, "jan" }, { 2, "feb" }, { 3, "mar" }, { 4, "apr" },

    { 5, "may" }, { 6, "jun" }, { 7, "jul" }, { 8, "aug" },

    { 9, "sep" }, {10, "oct" }, {11, "nov" }, {12, "dec" }

};



#define nr_of_months (sizeof(months)/sizeof(months[0]))



static int

compmi(const void *m1, const void *m2)

{

    struct mi *mi1 = (struct mi *) m1;

    struct mi *mi2 = (struct mi *) m2;

    return strcmp(mi1->name, mi2->name);

}



int

main(int argc, char **argv)

{

    int i;



    qsort(months, nr_of_months, sizeof(struct mi), compmi);

    for (i = 1; i < argc; i++) {

        struct mi key, *res;

        key.name = argv[i];

        res = bsearch(&key, months, nr_of_months,

                      sizeof(struct mi), compmi);

        if (res == NULL)

            printf("'%s': unknown month\n", argv[i]);

        else

            printf("%s: month #%d\n", res->name, res->nr);

    }

    exit(EXIT_SUCCESS);

}

´ØÏ¢¹àÌÜ

hsearch(3), lsearch(3), qsort(3), tsearch(3)