Day 5

day5/src/main.rs

@@ -0,0 +1,117 @@
+use std::fs::File;
+use std::io::{prelude::*, BufReader};
+
+#[derive(Clone, Debug)]
+struct Crate {
+    label: String,
+}
+
+#[derive(Clone, Debug)]
+struct GameBoard {
+    labels: Vec<String>,
+    board: Vec<Vec<Crate>>,
+}
+
+impl GameBoard {
+    fn game1_move(&mut self, count: usize, from: usize, to: usize) {
+        let ref mut v: Vec<Crate> = Vec::new();
+        let work = self.board.get_mut(from - 1).unwrap();
+        for _ in 0..count {
+            v.push(work.pop().unwrap());
+        }
+        let work = self.board.get_mut(to - 1).unwrap();
+        for _ in 0..count {
+            work.append(v);
+        }
+    }
+    fn game2_move(&mut self, count: usize, from: usize, to: usize) {
+        let ref mut v: Vec<Crate> = Vec::new();
+        let work = self.board.get_mut(from - 1).unwrap();
+        for _ in 0..count {
+            v.push(work.pop().unwrap());
+        }
+        v.reverse();
+        let work = self.board.get_mut(to - 1).unwrap();
+        for _ in 0..count {
+            work.append(v);
+        }
+    }
+    fn get_tops(&self) -> String {
+        self.board
+            .iter()
+            .map(|x| x.last().unwrap().label.clone())
+            .fold("".to_string(), |acc, x| acc + &x)
+    }
+}
+impl From<Vec<String>> for GameBoard {
+    fn from(v: Vec<String>) -> Self {
+        let mut board_vec = v.clone();
+        let label_vec = board_vec.pop().unwrap();
+        // get labels
+        let labels = label_vec
+            .split_whitespace()
+            .map(|x| x.to_string())
+            .collect::<Vec<String>>();
+        //TODO sscanf for crates
+        board_vec.reverse();
+        let mut board = vec![Vec::new(); labels.len()];
+        board_vec.iter().for_each(|line| {
+            board.iter_mut().enumerate().for_each(|(i, col)| {
+                let (begin, end) = (i * 4, std::cmp::min(i * 4 + 4, line.len()));
+                let crate_str = line[begin..end]
+                    .to_string()
+                    .matches(char::is_alphabetic)
+                    .collect::<String>();
+                if !crate_str.is_empty() {
+                    col.push(Crate { label: crate_str });
+                }
+            })
+        });
+        GameBoard { labels, board }
+    }
+}
+
+fn main() -> std::io::Result<()> {
+    //Read in file
+    let file = File::open("input")?;
+    let reader = BufReader::new(file);
+
+    //read in the parts of the file
+    let (board_lines, movement_lines, _) = reader.lines().fold(
+        (Vec::new(), Vec::new(), false),
+        |mut acc: (Vec<String>, Vec<String>, bool), line| {
+            let line = line.unwrap();
+            if line.is_empty() {
+                acc.2 = true;
+            } else if acc.2 {
+                acc.1.push(line);
+            } else {
+                acc.0.push(line);
+            }
+            acc
+        },
+    );
+    println!("{:?}", board_lines);
+    let mut board = GameBoard::from(board_lines);
+
+    movement_lines.iter().for_each(|line| {
+        match line
+            .split_whitespace()
+            .filter_map(|x| x.parse::<usize>().ok())
+            .collect::<Vec<usize>>()[..]
+        {
+            [count, from, to] => board.game2_move(count, from, to),
+            _ => panic!(
+                "{:#?} {:?}",
+                board,
+                line.matches(char::is_numeric)
+                    .map(|x| x.parse::<usize>().unwrap())
+                    .collect::<Vec<usize>>()
+            ),
+        };
+    });
+
+    println!("{}", board.get_tops());
+
+    Ok(())
+}