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#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));
}
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