星めぐり 〜 第2回 ESM オフラインどう書く 例題 回答

star.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

static const unsigned char Direction[10][2] = {
/*  R ,  W */
  {'H', 'I'}, /*A*/
  {'D', 'G'}, /*B*/
  {'J', 'A'}, /*C*/
  {'F', 'I'}, /*D*/
  {'B', 'C'}, /*E*/
  {'H', 'A'}, /*F*/
  {'D', 'E'}, /*G*/
  {'J', 'C'}, /*H*/
  {'F', 'G'}, /*I*/
  {'B', 'E'}, /*J*/
};

int next(const unsigned char* color, unsigned char* route){
  return (*color != 0x00) &&
         (*route = Direction[*route++ - 'A'][*color & 0x01]) &&
         next(++color, route);
}

void trace(const unsigned char* input, unsigned char* route){
  *route = *input;
  next(++input, route);
}

void test(const unsigned char* input, const unsigned char* expected) {
  unsigned char* actual = (unsigned char*)calloc(strlen(input) + 1,
      sizeof(unsigned char));

  trace(input, actual);

  printf("%s %s %s\n",
      !strcmp(expected, actual) ? "\033[32mOK\033[39m" : "\033[31mNG\033[39m",
      expected, actual);

  free(actual);
}

int main(int argc, char* argv[]){
  test("AW", "AI");
  test("GR", "GD");
  test("GW", "GE");
  test("IR", "IF");
  test("HR", "HJ");
  test("BWW", "BGE");
  test("ARW", "AHC");
  test("GRR", "GDF");
  test("BWR", "BGD");
  test("JWWW", "JECA");
  test("DRRR", "DFHJ");
  test("CWWR", "CAIF");
  test("HWWW", "HCAI");
  test("GWRWR", "GEBGD");
  test("FRRRW", "FHJBG");
  test("JRRWW", "JBDIG");
  test("JWWRRW", "JECJBG");
  test("GRRRWW", "GDFHCA");
  test("BRWRWR", "BDIFAH");
  test("IRWRRWR", "IFAHJEB");
  test("IWWWRRW", "IGECJBG");
  test("GWWRWWR", "GECJECJ");
  test("HRRWRWRW", "HJBGDIFA");
  test("FRWWWRRW", "FHCAIFHC");
  test("HRWWWRWRW", "HJECAHCJE");
  test("CWWWRRWWW", "CAIGDFAIG");
  test("BRRRWRRRRW", "BDFHCJBDFA");
  test("FRWRRWRRWW", "FHCJBGDFAI");
  test("GWRRRRWRWRW", "GEBDFHCJEBG");
  test("DRWWWWWWRRW", "DFAIGECAHJE");
  test("ARRRRWRRRRWW", "AHJBDIFHJBGE");
  test("AWWWWWWRRWRR", "AIGECAIFHCJB");
  test("JWWWRRWRWRWWR", "JECAHJEBGDIGD");
  test("CRWRWRRWWWRWW", "CJEBGDFAIGDIG");
  test("DWRWRWRWRWWRWW", "DIFAHCJEBGEBGE");
  test("GRWWWRRRRWRWRR", "GDIGEBDFHCJEBD");
  test("ARWWWRWWRWWWWWW", "AHCAIFAIFAIGECA");
  test("DWRWRRWRWWRWWRW", "DIFAHJEBGEBGEBG");
  test("JRWRRRRRWRRRRRWR", "JBGDFHJBGDFHJBGD");
  test("IRWWRRWWWWWRRWWR", "IFAIFHCAIGEBDIGD");

  return 0;
}