2022 day 12 (C, parts 1 & 2)

2022/RESULTS.txt

@@ -261,7 +261,15 @@ aoc.bash: res=408
 	time: 0:00.81 real, 0.80 user, 0.00 sys
 	context-switch:	223+1, page-faults: 0+486
 
+aoc-c: res=408
+	time: 0:00.00 real, 0.00 user, 0.00 sys
+	context-switch:	0+1, page-faults: 0+170
+
 +++++++++++++++++ part 2
 aoc.bash: res=399
-	time: 0:00.57 real, 0.56 user, 0.00 sys
+	time: 0:00.55 real, 0.54 user, 0.01 sys
-	context-switch:	35+1, page-faults: 0+459
+	context-switch:	25+1, page-faults: 0+460
+
+aoc-c: res=399
+	time: 0:00.00 real, 0.00 user, 0.00 sys
+	context-switch:	0+1, page-faults: 0+171

2022/day12/Makefile

@@ -28,7 +28,7 @@ export LD_LIBRARY_PATH = $(LIBDIR)
 
 CFLAGS  += -std=gnu11
 CFLAGS  += -O2
-CFLAGS  += -g
+#CFLAGS  += -g
 # for gprof
 # CFLAGS += -pg
 CFLAGS  += -Wall
@@ -50,7 +50,7 @@ VALGRINDFLAGS := --leak-check=full --show-leak-kinds=all --track-origins=yes \
 TIME    := \time -f "\ttime: %E real, %U user, %S sys\n\tcontext-switch:\t%c+%w, page-faults: %F+%R\n"
 export PATH := .:$(PATH)
 
-.PHONY: clean all compile assembly memcheck memcheck1 memcheck2 part1 part2 ccls bear org
+.PHONY: clean cleanall all compile assembly memcheck memcheck1 memcheck2 part1 part2 ccls bear org
 
 all: README.org ccls part1 part2
 
@@ -80,7 +80,10 @@ part2: aoc-c
 ccls: $(CCLSFILE)
 
 clean:
-	@rm -f aoc-c core* vgcore* gmon.out aoc-c.s aoc-c.i README.html compile_commands.json
+	@rm -f aoc-c core* vgcore* gmon.out aoc-c.s aoc-c.i README.html
+
+cleanall: clean
+	@rm -f compile_commands.json
 
 aoc-c: aoc-c.c common.c
 	@echo compiling $<

2022/day12/aoc-c.c

@@ -0,0 +1,172 @@
+/* aoc-c.c: Advent of Code 2022, day 12
+ *
+ * Copyright (C) 2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "br.h"
+#include "list.h"
+#include "pool.h"
+
+#include "aoc.h"
+
+#define MAX_LINES 128                             /* should be dynamic */
+
+typedef struct coord {
+    int x, y;
+} coord_t;
+
+typedef struct square {
+    char height;
+    int dfs;
+    coord_t coord;
+    struct list_head queue;
+} square_t;
+
+typedef struct grid {
+    int nx, ny;
+    coord_t start, end;
+
+    square_t **map;
+} grid_t;
+
+pool_t *pool_lines;
+LIST_HEAD(dfs);
+
+#define CELL(g, x, y) (&(g)->map[y][x])
+
+static inline void push(square_t *s)
+{
+    list_add_tail(&s->queue, &dfs);
+}
+
+static inline square_t *pop()
+{
+    square_t *s = list_first_entry_or_null(&dfs, square_t, queue);
+    if (s)
+        list_del(&s->queue);
+    return s;
+}
+
+static int parse(grid_t *grid)
+{
+    size_t alloc = 0;
+    ssize_t buflen;
+    char *buf = NULL;
+    int line = 0;
+    square_t *pline;
+
+    while ((buflen = getline(&buf, &alloc, stdin)) > 0) {
+        buf[--buflen] = 0;
+        if (line == 0) {
+            pool_lines = pool_create("lines", 128, buflen * sizeof(square_t));
+            grid->nx = buflen;
+        }
+        grid->map[line] = pool_get(pool_lines);
+        pline = grid->map[line];
+        for (int i = 0; i < buflen; ++i) {
+            pline[i].coord.x = i;
+            pline[i].coord.y = line;
+            pline[i].dfs = 0;
+            if (buf[i] == 'S') {
+                grid->start.x = i;
+                grid->start.y = line;
+                pline[i].height = 'a';
+            } else if (buf[i] == 'E') {
+                grid->end.x = i;
+                grid->end.y = line;
+                pline[i].height = 'z';
+            } else {
+                pline[i].height = buf[i];
+            }
+        }
+        line++;
+    }
+    grid->ny = line;
+    free(buf);
+    return 1;
+}
+
+static square_t *dfs_add(grid_t *g, square_t *s, int n)
+{
+    static coord_t dirs[4] = { { 0, -1 }, { 1, 0 }, { 0, 1 }, { -1, 0 } };
+    int x = s->coord.x + dirs[n].x, y = s->coord.y + dirs[n].y;
+    square_t *ret = NULL;
+    if (x >= 0 && y >= 0 && x < g->nx && y < g->ny) {
+        ret = CELL(g, x, y);
+        if (!ret->dfs)
+            return ret;
+    }
+    return NULL;
+}
+
+static int part1(grid_t *g)
+{
+    square_t *s, *n;
+
+    s = CELL(g, g->start.x, g->start.y);
+    s->dfs = 1;
+    push(s);
+    while((s = pop())) {
+        //log_f(3, "");
+        for (int i = 0; i < 4; i++) {
+            if (!(n = dfs_add(g, s, i)))
+                continue;
+            if (n->height <= s->height+1) {
+                if (n->coord.x == g->end.x && n->coord.y == g->end.y)
+                    return s->dfs;
+                n->dfs = s->dfs + 1;
+                push(n);
+            }
+
+        }
+    }
+    return -1;
+}
+
+static int part2(grid_t *g)
+{
+    square_t *s, *n;
+    //int ret = 0;
+    s = CELL(g, g->end.x, g->end.y);
+    s->dfs = 1;
+    push(s);
+    while((s = pop())) {
+        //log_f(3, "");
+        for (int i = 0; i < 4; i++) {
+            if (!(n = dfs_add(g, s, i)))
+                continue;
+            if (n->height >= s->height - 1) {
+                if (n->height == 'a')
+                    return s->dfs;
+                n->dfs = s->dfs + 1;
+                push(n);
+            }
+
+        }
+    }
+    return -1;
+}
+
+
+int main(int ac, char **av)
+{
+    int part = parseargs(ac, av);
+    square_t *board[MAX_LINES];
+    grid_t grid = { 0, 0, { 0, 0 }, {0, 0}, board };
+
+    parse(&grid);
+    printf("%s: res=%d\n", *av, part == 1? part1(&grid): part2(&grid));
+    pool_destroy(pool_lines);
+    exit(0);
+}