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authornekineki <nekineki@nekineki.net>2022-12-11 14:47:27 +0100
committernekineki <nekineki@nekineki.net>2022-12-11 14:50:32 +0100
commitfe75c10e350743a1c078f065d69556fecf825ca5 (patch)
tree956556a564c9329346dc9d8b1535dc5e365f3d55 /2022/day06.c
parenta74d2dc54aef546664bcc8c81eb8e01a93e94391 (diff)
move files around, update paths
Diffstat (limited to '2022/day06.c')
-rw-r--r--2022/day06.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/2022/day06.c b/2022/day06.c
new file mode 100644
index 0000000..5e79b72
--- /dev/null
+++ b/2022/day06.c
@@ -0,0 +1,54 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include "util.h"
+
+// char filename[] = "in/day06.ref";
+char filename[] = "in/day06.pzl";
+
+#define BUF_LEN 10000
+u8 buf[BUF_LEN];
+#define NAH_LEN 26
+u8 not_a_hashmap[NAH_LEN];
+
+s32 solve(u32 n)
+{
+ int fd = open(filename, O_RDONLY);
+ u32 data_len = read(fd, buf, LEN(buf));
+ if (data_len == LEN(buf)) {
+ printf("buffer probably not big enough\n");
+ exit(1);
+ }
+
+ for (u32 i = n; i < data_len; ++i) {
+ memset(not_a_hashmap, 0x00, LEN(not_a_hashmap));
+
+ for (u32 j = 1; j <= n; ++j) {
+ u32 index = (buf[i-j]-'a');
+ if (index >= NAH_LEN) {
+ printf("nah too small\n");
+ exit(1);
+ }
+ not_a_hashmap[index] = 1;
+ }
+
+ u32 sum = 0;
+ for (u32 j = 0; j < NAH_LEN; ++j) {
+ sum += not_a_hashmap[j];
+ }
+ if (sum == n) {
+ return i;
+ }
+
+ }
+ return -1;
+}
+
+int main()
+{
+ printf("res1: %d\n", solve(4));
+ printf("res2: %d\n", solve(14));
+}
+