gistfile1.txt

#include <stdlib.h>

extern unsigned int keylookup[];
extern char *       toASCIILut[];

int comparator(const void * key, const void * member) {
  unsigned int keyU = (*((unsigned int*) key));
  unsigned int memberU = (*((unsigned int *) member));

  if        (keyU < memberU) {
    return -1;
  } else if (keyU > memberU) {
    return 1;
  }
  return 0;
}

char * findString(unsigned int index) {
  unsigned int * out_index = bsearch(&index, &keylookup, 8922, sizeof(unsigned int), &comparator);

  if (out_index==NULL) {
    // not found
    return "";
  } else {
    return toASCIILut[out_index - keylookup];
  }
}