binary_search.c

#include <stdio.h>

typedef struct Nameval Nameval;
struct Nameval {
  char *name;
  int value;
};

int lookup(char *word, Nameval st[], int sts) {

  int low, hight, mid, cmp;
  low = 0;
  hight = sts + 1;
  while (low <= hight) {
    mid = (low + hight) / 2;
    cmp = strcmp(word, st[mid].name);
    if (cmp < 0)
      hight = mid - 1;
    else if (cmp > 0)
      low = mid + 1;
    else
      return st[mid].value;
  }
  return 0;
}

int main (int argc, const char * argv[])
{
  Nameval stock[] = {
    "Backup", 1,
    "Desktop", 2,
    "Documents", 3,
    "Downloads", 4,
    "Dropbox", 5,
    "Library", 6,
    "Movies", 7,
    "Music", 8,
    "OF", 9,
    "Pankaku", 10,
    "Pictures", 11,
    "Public", 12,
    "Sites", 13,
    "bin", 14,
    "doc", 15,
    "git", 16,
    "macports", 17,
    "parse", 18,
    "pic", 19,
    "share", 20,
    "tmp", 21,
  };

  char *target = "git";
  int result = lookup(target, stock, 20);
  printf("%d", result);

  return 0;
}