advent2023

commit f18e52045ff61ae209f1752859199ceb4648743f
parent 1d5eca68ec86d199104f69fdce05efe876bceb28
Author: bsandro <email@bsandro.tech>
Date:   Wed, 10 Jan 2024 22:12:20 +0200

merge day10 -> master

Diffstat:
M
day10/main.c
 | 
1
-
M
day10/puzzle.c
 | 
92
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------

2 files changed, 80 insertions(+), 13 deletions(-)
diff --git a/day10/main.c b/day10/main.c
@@ -1,7 +1,6 @@
 #include <stdio.h>
 #include <time.h>
 #include <string.h>
-#include <threads.h>
 
 void puzzle(const char *filename, long long *res1, long long *res2);
 //void puzzle_test(const char *filename, long long *res1, long long *res2);
diff --git a/day10/puzzle.c b/day10/puzzle.c
@@ -12,6 +12,39 @@
 
 #define STR_LEN 2048
 
+typedef struct Stack {
+	char *data;
+	int len;
+} Stack;
+
+void stack_push(Stack *s, char c) {
+	assert(s!=NULL);
+	s->len += sizeof(char);
+	s->data = realloc(s->data, s->len);
+	s->data[s->len-1] = c;
+}
+
+char stack_pop(Stack *s) {
+	assert(s!=NULL);
+	if (s->len==0) return 0;
+	s->len--;
+	char r = s->data[s->len];
+	s->data = realloc(s->data, s->len);
+	return r;
+}
+
+char stack_last(Stack *s) {
+	assert(s!=NULL);
+	if (s->len==0) return 0;
+	return s->data[s->len-1];
+}
+
+void stack_free(Stack *s) {
+	assert(s!=NULL);
+	free(s->data);
+	s->len = 0;
+}
+
 typedef enum Dir {
 	DIR_INVALID,
 	DIR_NORTH,
@@ -147,31 +180,66 @@ int traverse(Map *map, Pos start, Map *loop) {
 }
 
 /*
-
-| -> |,F
+| -> |,F,L
 L -> J
 F -> 7
+7 -> |,F,L
+ */
+bool is_wall_toggles(char cur, char prev) {
+	if (cur=='-') return false;
+	//if (cur=='|') return prev!=0;
+
+	if (cur=='J') return prev=='L';
+	if (cur=='L') return prev=='J';
 
+	if (cur=='7') return prev=='F';
+	if (cur=='F') return prev=='7';
+
+	return false; //prev=='|';
+}
+
+/*
+F -> J
+L -> 7
  */
+bool is_wall_continues(char cur, char prev) {
+	if (cur=='J') return prev=='F';
+	if (cur=='7') return prev=='L';
+	return false;
+}
 
 // | L J F 7 S
 int calc_area(Map *loop) {
 	int area = 0;
 	for (int y=0; y<loop->h; ++y) {
-		char open_sym = 0;
+		Stack walls={.data=NULL,.len=0};
+		bool is_open = false;
 		for (int x=0; x<loop->w; ++x) {
 			char sym = loop->area[loop->w*y+x];
-			if (open_sym==0) {
-				if (sym=='|'||sym=='F'||sym=='L'||sym=='S') {
-					open_sym = sym;
-				}
-			} else {
-				if (sym=='.') {
+			char prev = stack_last(&walls);
+
+			if (sym=='.') {
+			 	if (is_open) {
 					loop->area[loop->w*y+x] = 'I';
 					area++;
-				} else if (sym=='|'||sym=='J') {
-					open_sym = 0;
-				} //else if () {}
+				}
+				continue;
+			}
+
+			if (is_wall_continues(sym, prev)) {
+				//printf("[%2d:%2d] wall continues from %c to %c (%d)\n", y, x, prev, sym, is_open);
+				//stack_pop(&walls);
+				//prev = stack_pop(&walls);
+				stack_push(&walls, sym);
+				//is_open = !is_open;
+			} else if (sym!='-') {
+				is_open = !is_open;
+				stack_push(&walls, sym);
+				if (is_open) {
+					printf("[%2d:%2d] wall opened from %c to %c (%d)\n", y, x, prev, sym, is_open);
+				} else {
+					printf("[%2d:%2d] wall closed from %c to %c (%d)\n", y, x, prev, sym, is_open);
+				}
 			}
 		}
 	}