Fixed naming for 10+ challenges

1 files changed, 156 insertions, 0 deletions

diff --git a/2020/04/solve.c b/2020/04/solve.c
new file mode 100644
index 0000000..a613660
--- /dev/null
+++ b/2020/04/solve.c
@@ -0,0 +1,156 @@
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+void normalize(char *data)
+{
+	for (char *p = data; *p; p++) {
+		if (*p == '\n' && *(p + 1) == '\n') {
+			*p = ' ';
+			p++;
+		} else if (*p == '\n') {
+			*p = ' ';
+		}
+	}
+}
+
+char *valid[] = { "byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid" };
+char *valid_colors[] = { "amb", "blu", "brn", "gry", "grn", "hzl", "oth" };
+
+int part_one(char *data)
+{
+	int res = 0;
+
+	int correct = 0;
+	for (char *p = data; *p; p++) {
+		if (*p == '\n') {
+			if (correct == 7)
+				res++;
+			correct = 0;
+			continue;
+		}
+
+		char key[4] = { 0 };
+		char value[16] = { 0 };
+		sscanf(p, "%3[^:]:%s ", key, value);
+
+		for (int i = 0; i < sizeof(valid) / sizeof(valid[0]); ++i) {
+			if (!strcmp(key, valid[i])) {
+				correct++;
+				break;
+			}
+		}
+
+		p += 3 + strlen(value) + 1;
+		if (*(p + 1) == '\0') {
+			if (correct == 7)
+				res++;
+		}
+	}
+
+	return res;
+}
+
+#define EQ(a, b) (!strcmp((a), (b))) // String equality
+#define BR(x) ((x) >= 1920 && (x) <= 2002) // Birth rule
+#define IR(x) ((x) >= 2010 && (x) <= 2020) // Issue rule
+#define ER(x) ((x) >= 2020 && (x) <= 2030) // Expiration rule
+#define HR(x) ((x) >= 150 && (x) <= 193) // Height rule
+#define CR(x)                                                                                      \
+	(EQ(x, "amb") || EQ(x, "blu") || EQ(x, "brn") || EQ(x, "gry") || EQ(x, "grn") ||           \
+	 EQ(x, "hzl") || EQ(x, "oth")) // Eye color rule
+// BTW: I hate gotos
+int part_two(char *data)
+{
+	int res = 0;
+
+	int correct = 0;
+	for (char *p = data; *p; p++) {
+		if (*p == '\n') {
+			if (correct == 7)
+				res++;
+			correct = 0;
+			continue;
+		}
+		char key[4] = { 0 };
+		char value[16] = { 0 };
+		sscanf(p, "%3[^:]:%s ", key, value);
+
+		// General value verification/parsing
+		int y = 0;
+		if (EQ(key, "byr") || EQ(key, "iyr") || EQ(key, "eyr")) {
+			if (!sscanf(value, "%4d", &y))
+				goto invalid;
+		} else if (EQ(key, "hgt")) {
+			char last = value[strlen(value) - 1];
+			if (last == 'm') {
+				sscanf(value, "%dcm", &y);
+			} else if (last == 'n') {
+				sscanf(value, "%din", &y);
+				y = (int)roundf(((float)y * 2.54)); // lol
+			} else {
+				goto invalid;
+			}
+		} else if (EQ(key, "hcl") && (strlen(value) != 7 || !sscanf(value, "#%6x", &y))) {
+			goto invalid;
+		} else if (EQ(key, "ecl")) {
+			char c[4];
+			if (!sscanf(value, "%3s", c) || !CR(c))
+				goto invalid;
+		} else if (EQ(key, "pid")) {
+			if (!sscanf(value, "%9d", &y))
+				goto invalid;
+		}
+
+		// Number range verification
+		if (EQ(key, "byr") && !BR(y))
+			goto invalid;
+		else if (EQ(key, "iyr") && !IR(y))
+			goto invalid;
+		else if (EQ(key, "eyr") && !ER(y))
+			goto invalid;
+		else if (EQ(key, "hgt") && !HR(y)) {
+			goto invalid;
+		}
+
+		for (int i = 0; i < sizeof(valid) / sizeof(valid[0]); ++i) {
+			if (!strcmp(key, valid[i])) {
+				correct++;
+				break;
+			}
+		}
+
+		goto next;
+
+	invalid:
+		/* printf("Invalid: %s:%s (y=%d)\n", key, value, y); */
+		correct = -42; // Awesome fix!
+	next:
+		p += 3 + strlen(value) + 1;
+		if (*(p + 1) == '\0') {
+			if (correct == 7)
+				res++;
+		}
+	}
+
+	return res;
+}
+
+#define SIZE 20000
+int main(int argc, char *argv[])
+{
+	FILE *fp = fopen("input", "r");
+	if (!fp)
+		exit(EXIT_FAILURE);
+	char buf[SIZE] = { 0 };
+	fread(buf, SIZE, 1, fp);
+	normalize(buf);
+
+	printf("%d\n", part_one(buf));
+	printf("%d\n", part_two(buf));
+
+	fclose(fp);
+	return 0;
+}