day 10 part 1 (with tons of debug information ;-)

2021/day10/aoc-c.c

@@ -0,0 +1,142 @@
+/* aoc-c: Advent2021 game, day 6 parts 1 & 2
+ *
+ * Copyright (C) 2021 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 <unistd.h>
+#include <string.h>
+#include <malloc.h>
+
+#include "debug.h"
+#include "bits.h"
+#include "list.h"
+#include "pool.h"
+
+static char stack[1024];
+static size_t nstack;
+
+inline static int push(char c)
+{
+    stack[nstack++] = c;
+    printf("push(%c)\n", c);
+    return c;
+}
+
+inline static int pop()
+{
+    int c;
+    if (!nstack)
+        return 0;
+    c = stack[--nstack];
+    printf("pop(%c)\n", c);
+
+    return c;
+}
+
+struct match {
+    char open;
+    char close;
+    int value;
+} syntax[] = {
+    { '(', ')', 3 },
+    { '[', ']', 57 },
+    { '{', '}', 1197 },
+    { '<', '>', 25137 },
+};
+
+inline static int match(char c)
+{
+    int co;
+    size_t i;
+
+    if (!(co = pop()))
+        return 0;
+    for (i = 0; i < sizeof(syntax); ++i)
+        if (syntax[i].close == c && co != syntax[i].open)
+            return syntax[i].value;
+    return 0;
+}
+
+static u64 part1()
+{
+    char *buf = NULL, *p;
+    size_t alloc;
+    ssize_t len;
+    u64 res = 0;
+
+    while ((len = getline(&buf, &alloc, stdin)) > 0) {
+        nstack = 0;
+        buf[len - 1] = 0;
+        p = buf;
+        while (*p) {
+            switch (*p) {
+                case '{':
+                case '(':
+                case '[':
+                case '<':
+                    push(*p);
+                    break;
+                case '}':
+                case ')':
+                case ']':
+                case '>':
+                    res += match(*p);
+            }
+            p++;
+        }
+    }
+    return res;
+}
+
+static u64 part2()
+{
+    return 1;
+}
+
+static u64 doit(int part)
+{
+    return part == 1? part1(): part2();
+}
+
+static int usage(char *prg)
+{
+    fprintf(stderr, "Usage: %s [-d debug_level] [-p part]\n", prg);
+    return 1;
+}
+
+int main(int ac, char **av)
+{
+    int opt;
+    u32 exercise = 1;
+    u64 res;
+
+    while ((opt = getopt(ac, av, "d:p:")) != -1) {
+        switch (opt) {
+            case 'd':
+                debug_level_set(atoi(optarg));
+                break;
+            case 'p':                             /* 1 or 2 */
+                exercise = atoi(optarg);
+                if (exercise < 1 || exercise > 2)
+                    return usage(*av);
+                break;
+            default:
+                return usage(*av);
+        }
+    }
+    if (optind < ac)
+        return usage(*av);
+
+    res = doit(exercise);
+    printf("%s : res=%lu\n", *av, res);
+    exit (0);
+}