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-rw-r--r--Makefile4
-rw-r--r--god_hands.c176
-rw-r--r--main.c145
3 files changed, 178 insertions, 147 deletions
diff --git a/Makefile b/Makefile
index 2a405f9..fa5f19a 100644
--- a/Makefile
+++ b/Makefile
@@ -1,9 +1,9 @@
CC = gcc
CFLAGS = -Wall -W -std=c99 -g
-god_hands_solver: main.o
+god_hands_solver: god_hands.o
$(CC) -o $@ $^ $(LDFLAGS)
-main.o: main.c
+god_hands.o: god_hands.c
$(CC) -o $@ -c $< $(CFLAGS)
diff --git a/god_hands.c b/god_hands.c
new file mode 100644
index 0000000..4ff2f5d
--- /dev/null
+++ b/god_hands.c
@@ -0,0 +1,176 @@
+#include <stdint.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include <stdbool.h>
+
+typedef uint8_t byte;
+typedef int8_t rang_t;
+
+typedef struct {
+ byte value;
+ rang_t rang;
+} elem_t;
+
+typedef struct {
+ int len;
+ elem_t *elem;
+} map_t;
+
+map_t *map_g;
+
+/* resolve {{{ */
+
+/* returns true if the map is empty, otherwise returns false */
+static bool map_is_empty(void)
+{
+ for (int i = 0; i < map_g->len; i++) {
+ if (map_g->elem[i].rang == -1) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+/* return the index of the next element */
+static inline int get_next_case(int current)
+{
+ return (current + map_g->elem[current].value) % map_g->len;
+}
+
+/* return the index of the previous element */
+static inline int get_prev_case(int current)
+{
+ int prev = current - map_g->elem[current].value;
+
+ if (current < map_g->elem[current].value)
+ prev += map_g->len;
+
+ return prev;
+}
+
+static int perform_resolve_god_hands(int activated, int offset)
+{
+ int next, prev;
+
+ /* this one is already activated, not possible captain */
+ if (map_g->elem[activated].rang != -1) {
+ return -1;
+ }
+
+ /* activate the current case */
+ map_g->elem[activated].rang = offset;
+
+ if (map_is_empty()) {
+ /* we won */
+ return 0;
+ }
+
+ next = get_next_case(activated);
+ prev = get_prev_case(activated);
+
+ if (perform_resolve_god_hands(next, offset + 1) == 0)
+ return 0;
+
+ if (perform_resolve_god_hands(prev, offset + 1) == 0)
+ return 0;
+
+ /* reset to default */
+ map_g->elem[activated].rang = -1;
+ return -1;
+}
+
+int solve_god_hands(map_t *map)
+{
+ for (int i = 0; i < map->len; i++) {
+ map->elem[i].rang = -1;
+ }
+
+ map_g = map;
+
+ for (int i = 0; i < map->len; i++) {
+ if (perform_resolve_god_hands(i, 0) == 0) {
+ return 0;
+ }
+ }
+
+ return -1;
+}
+
+/* }}} */
+
+static void display_solution(const map_t *map)
+{
+ for (int i = 0; i < map->len; i++) {
+ /* run through the order */
+ for (int j = 0; j < map->len; j++) {
+ /* run through the elems */
+
+ assert (map->elem[j].rang != -1);
+
+ if (map->elem[j].rang == i) {
+ printf("[%d] ", j);
+ break;
+ }
+ }
+ }
+ putchar('\n');
+}
+
+int main(void)
+{
+ map_t map;
+ char buffer[16];
+
+ /* get the length of the map */
+ for (;;) {
+ if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
+ fputs("size of the map: ", stdout);
+ }
+
+ if (fgets(buffer, sizeof(buffer), stdin) == NULL) {
+ return 0;
+ }
+
+ /* TODO replace with strtol to handle errors of type 42(.*) */
+ map.len = atoi(buffer);
+
+ if (map.len <= 0) {
+ fprintf(stderr, "the map has an invalid size\n");
+
+ if (!isatty(STDIN_FILENO))
+ return -1;
+
+ continue;
+ }
+
+ break;
+ }
+
+ map.elem = malloc(sizeof(elem_t) * map.len);
+
+ for (int i = 0; i < map.len; i++) {
+ if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO))
+ printf("(%02d/%02d): ", i + 1, map.len);
+
+ fflush(stdout);
+
+ if (fgets(buffer, sizeof(buffer), stdin) == NULL) {
+ return 0;
+ }
+
+ /* TODO check for errors (i.e. not numbers and negative values */
+ map.elem[i].value = atoi(buffer);
+ }
+
+ if ((solve_god_hands(&map)) != 0) {
+ fputs("cannot solve the paradox, kupo :-/\n", stderr);
+ } else {
+ fputs("we solved the paradox kupo! :-)\n", stdout);
+ display_solution(&map);
+ }
+
+ return 0;
+}
diff --git a/main.c b/main.c
deleted file mode 100644
index f359678..0000000
--- a/main.c
+++ /dev/null
@@ -1,145 +0,0 @@
-#include <stdint.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <assert.h>
-#include <stdbool.h>
-
-typedef uint8_t byte;
-typedef int8_t rang_t;
-
-typedef struct {
- byte value;
- rang_t rang;
-} elem_t;
-
-typedef struct {
- int len;
- elem_t *elem;
-} map_t;
-
-map_t *map_g;
-
-/* resolve {{{ */
-
-static bool map_is_empty(void)
-{
- for (int i = 0; i < map_g->len; i++) {
- if (map_g->elem[i].rang == -1) {
- return false;
- }
- }
-
- return true;
-}
-
-static inline int get_next(int current)
-{
- return (current + map_g->elem[current].value) % map_g->len;
-}
-
-static inline int get_prev(int current)
-{
- int prev = current - map_g->elem[current].value;
-
- if (current < map_g->elem[current].value)
- prev += map_g->len;
-
- return prev;
-}
-
-static int perform_resolve_god_hands(int activated, int offset)
-{
- int next, prev;
-
- /* this one is already activated, not possible captain */
- if (map_g->elem[activated].rang != -1) {
- return -1;
- }
-
- /* activate the current case */
- map_g->elem[activated].rang = offset;
-
- if (map_is_empty()) {
- /* we won */
- return 0;
- }
-
- next = get_next(activated);
- prev = get_prev(activated);
-
- if (perform_resolve_god_hands(next, offset + 1) == 0)
- return 0;
-
- if (perform_resolve_god_hands(prev, offset + 1) == 0)
- return 0;
-
- /* reset to default */
- map_g->elem[activated].rang = -1;
- return -1;
-}
-
-int solve_god_hands(map_t *map)
-{
- for (int i = 0; i < map->len; i++) {
- map->elem[i].rang = -1;
- }
-
- map_g = map;
-
- for (int i = 0; i < map->len; i++) {
- if (perform_resolve_god_hands(i, 0) == 0) {
- return 0;
- }
- }
-
- return -1;
-}
-
-/* }}} */
-
-static void display_solution(const map_t *map)
-{
- for (int i = 0; i < map->len; i++) {
- /* run through the order */
- for (int j = 0; j < map->len; j++) {
- /* run through the elems */
-
- assert (map->elem[j].rang != -1);
-
- if (map->elem[j].rang == i) {
- printf("[%d] ", j);
- break;
- }
- }
- }
- putchar('\n');
-}
-
-int main(void)
-{
- map_t map;
- char buffer[16];
-
- if (isatty(0))
- fputs("size of the map: ", stdout);
- map.len = atoi(fgets(buffer, sizeof(buffer), stdin));
-
- map.elem = malloc(sizeof(elem_t) * map.len);
-
- for (int i = 0; i < map.len; i++) {
- if (isatty(0))
- printf("(%02d/%02d): ", i + 1, map.len);
- fflush(stdout);
- map.elem[i].value = atoi(fgets(buffer, sizeof(buffer), stdin));
- }
-
- if ((solve_god_hands(&map)) != 0) {
- fputs("cannot resolve paradox kupo\n", stderr);
- } else {
- fputs("we resolved the paradox kupo\n", stdout);
- display_solution(&map);
- }
-
- return 0;
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 00:26:20 +0000