advent2023

commit 6e2c82f8dbd4c7ae5590e0654f5b6932867421d8
parent 808cdc3ce6e41aa17cd4e11864b1014a84151097
Author: bsandro <email@bsandro.tech>
Date:   Fri,  1 Dec 2023 15:16:08 +0200

day 01 p2

Diffstat:
M
day01/puzzle.c
 | 
93
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------
A
day01/test1.txt
 | 
7
+++++++

2 files changed, 88 insertions(+), 12 deletions(-)
diff --git a/day01/puzzle.c b/day01/puzzle.c
@@ -6,9 +6,26 @@
 #include <string.h>
 #include <strings.h>
 #include <assert.h>
+#include <stdbool.h>
 
 #define STR_LEN 1024
 
+int get_digits_p1(const char *);
+int get_digits_p2(const char *);
+int pop_digit(const char *);
+
+bool is_digit(char b) {
+	return b>='0' && b<='9';
+}
+
+bool is_letter(char b) {
+	return b>='a' && b<='z';
+}
+
+static const char* digits[9] = {
+	"one", "two", "three", "four", "five", "six", "seven", "eight", "nine"
+};
+
 void puzzle(const char *filename, long long *result1, long long *result2) {
 	FILE *infile = fopen(filename, "r");
 	if (infile == NULL) {
@@ -20,20 +37,13 @@ void puzzle(const char *filename, long long *result1, long long *result2) {
 	unsigned int line_num = 0;
 
 	*result1 = 0;
+	*result2 = 0;
 
 	while (fgets(buf, STR_LEN, infile) != NULL) {
-		int len = strlen(buf);
-		int n1 = -1, n2 = -1;
-		for (int i=0; i < len; ++i) {
-			char b = buf[i];
-			if (b > 47 && b < 58) {
-				n2 = b-48;
-				if (n1==-1) n1=b-48;
-			}
-		}
-		int num = n1*10 + n2;
-		//printf("num:%d\n", num);
-		*result1 += num;
+		int num1 = get_digits_p1(buf);
+		int num2 = get_digits_p2(buf);
+		*result1 += num1;
+		*result2 += num2;
 		++line_num;
 		bzero(buf, STR_LEN);
 	}
@@ -42,4 +52,63 @@ void puzzle(const char *filename, long long *result1, long long *result2) {
 	fclose(infile);
 
 	(void)result2;
+	(void)digits;
+}
+
+int get_digits_p1(const char *str) {
+	int len = strlen(str);
+	int n1 = -1, n2 = -1;
+	for (int i=0; i<len; ++i) {
+		char b = str[i];
+		if (is_digit(b)) {
+			n2 = b-'0';
+			if (n1==-1) n1=b-'0';
+		}
+	}
+	return n1*10+n2;
+}
+
+int get_digits_p2(const char *str) {
+	(void)str;
+
+	int len = strlen(str);
+	int n1=-1, n2=-1, i=0;
+	(void)n2;
+	while (i<len) {
+		char b = str[i];
+		if (is_digit(b)) {
+			n2 = b-'0';
+			if (n1==-1) n1=b-'0';
+			++i;
+		} else if (is_letter(b)) {
+			int di = pop_digit(str+i);
+			if (di==-1) {
+				++i;
+			} else {
+				n2=di+1;
+				if (n1==-1) n1=n2;
+				//printf("(%d) found digit %d (%s) (len %d of %d) in %s (full %s)\n", i, di+1, digits[di], d_len, len, str+i, str);
+
+				// initial screwup, test was working but real data did not because of overlaps:)
+				//i+=d_len;
+				++i;
+			}
+		} else {
+			++i;
+		}
+	}
+
+	return n1*10+n2;
+}
+
+int pop_digit(const char *str) {
+	int len2 = strlen(str);
+	for (int i=0; i<9; ++i) {
+		int len1 = strlen(digits[i]);
+		if (len2<len1) continue;
+		if (strncmp(digits[i], str, len1) == 0) {
+			return i;
+		}
+	}
+	return -1;
 }
diff --git a/day01/test1.txt b/day01/test1.txt
@@ -0,0 +1,7 @@
+two1nine
+eightwothree
+abcone2threexyz
+xtwone3four
+4nineeightseven2
+zoneight234
+7pqrstsixteen