bsearch and qsort

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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=0;i<nr_of_months;i++)
        printf("%s/n", months[i].name);
     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);
     }
     return 0;
}

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