diff options
Diffstat (limited to 'day6/src')
-rw-r--r-- | day6/src/main.rs | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/day6/src/main.rs b/day6/src/main.rs new file mode 100644 index 0000000..46a148c --- /dev/null +++ b/day6/src/main.rs @@ -0,0 +1,36 @@ +use std::fs::File; +use std::io::{BufRead, BufReader}; + +fn main() -> std::io::Result<()> { + let file = File::open("input.txt")?; + let mut reader = BufReader::new(file); + let mut buffer = String::new(); + + reader.read_line(&mut buffer)?; + + let mut lanternfishes: Vec<_> = buffer + .trim() + .split(',') + .map(|x| x.parse::<i16>().unwrap()) + .collect::<Vec<i16>>(); + + for _ in 0..80 { + let mut n = 0; + for lanternfish in lanternfishes.iter_mut() { + if *lanternfish == 0 { + *lanternfish = 6; + n += 1; + } else { + *lanternfish -= 1; + } + } + + for _ in 0..n { + lanternfishes.push(8); + } + } + + println!("{}", lanternfishes.len()); + + Ok(()) +} |