Day 17 - task 1

res/17/test-input.txt

@@ -0,0 +1 @@
+>>><<><>><<<>><>>><<<>>><<<><<<>><>><<>>

src/days/d17.rs

@@ -1,12 +1,22 @@
 use std::fs;
 
 const WIDTH: usize = 7;
+const _TOTAL_ROCK_NUM: i64 = 2022;
 
 pub fn solve() {
     let path = "res/17/input.txt";
 
     let contents = fs::read_to_string(path).expect("I/O error, wrong path?");
 
+    // constant definition of rocks, from bottom to top
+    let rocks: Vec<Vec<(u8,u8)>> = vec![
+        vec![(0,0),(0,1),(0,2),(0,3)],
+        vec![(0,1),(1,0),(1,1),(1,2),(2,1)],
+        vec![(0,0),(0,1),(0,2),(1,2),(2,2)],
+        vec![(0,0),(1,0),(2,0),(3,0)],
+        vec![(0,0),(0,1),(1,0),(1,1)]
+    ];
+
     let directions: Vec<Dir> = contents
         .chars()
         .filter(|c| *c != '\n')
@@ -17,11 +27,174 @@ pub fn solve() {
         })
         .collect();
 
-    // [width][height]
-    let chamber = vec![Vec::<bool>::new(); WIDTH];
+    // [height][width]
+    let mut chamber = vec![vec![false;WIDTH];4];
+
+    let mut highest_rock = -1; // floor
+
+    let mut dir_iter = directions.iter();
+
+    let mut heights = Vec::<i64>::new();
+
+
+    /*
+    51 rocks 
+    
+    heights[50] - heights[15]
+    
+
+    (1_000_000_000_000 - 16) = 999_999_999_984
+    %
+    */
+
+
+
+    for i in 0..2344 {
+        // spawn new rock
+        let r_index = i as usize % rocks.len(); // get current rock index
+        let mut rock = Rock::new(&rocks[r_index], highest_rock);
+
+
+        while chamber.iter().filter(|row| !row.contains(&true)).count() < 7 {
+            chamber.push(vec![false;WIDTH])
+        }
+
+        loop {
+            // move to left or right
+            let next_dir = dir_iter.next();
+            let dir = match next_dir {
+                Some(x) => { x },
+                None => {
+                    dir_iter = directions.iter();
+                    dir_iter.next().unwrap()
+                }
+            };
+
+            match *dir {
+                Dir::Left => {
+                    if rock.left().valid_pos(&chamber) {
+                        rock = rock.left()
+                    }
+                },
+                Dir::Right => {
+                    if rock.right().valid_pos(&chamber) {
+                        rock = rock.right()
+                    }
+                }
+            }
+            // move down
+            if rock.down().valid_pos(&chamber) {
+                rock = rock.down();
+            } else {
+                rock.pos.iter().for_each(|coord| {
+                    chamber[coord.0 as usize][coord.1 as usize] = true
+                });
+                highest_rock = match chamber
+                    .iter()
+                    .enumerate()
+                    .filter(|row| row.1.contains(&true))
+                    .last() {
+                        Some(x) => x.0 as i64,
+                        None => -1
+                    };
+                // find recurring patterns in amount of rocks and height
+                heights.push(highest_rock);
+                //for i in 2..heights.len() {
+                //    test(i, &heights)
+                //}
+                break;
+            }
+        }
+    }
+    println!("Result 1: {}", highest_rock+1);
 }
 
+fn test(n: usize, heights: &Vec<i64>) {
+    if heights.len() % n == 0
+    && heights[heights.len()/n-1]*n as i64+n as i64 == heights[heights.len()-1]+1 {
+        println!("{}: {}", n, heights.len()/n)
+    }
+}
+
+fn _print_chamber(chamber: &Vec<Vec<bool>>, curr_rock: &Rock) {
+    let mut str_chamber: Vec<Vec<char>> = chamber.iter().map(|line| line.iter().map(|elem|
+        match *elem {
+            true => '#',
+            false => '.'
+        }
+    ).collect()).collect();
+
+    curr_rock.pos.iter().for_each(|pos| { str_chamber[pos.0 as usize][pos.1 as usize] = '@'; });
+
+    str_chamber.iter().rev().for_each(|str| println!("{}",str.iter().collect::<String>()))
+}
+
+#[derive(Clone, Debug)]
 enum Dir {
     Right,
     Left,
 }
+
+#[derive(Clone, Debug)]
+struct Rock {
+    pos: Vec<(i64,i64)>
+}
+
+impl Rock {
+    pub fn new(rock: &Vec<(u8,u8)>, highest_rock: i64) -> Self{
+        let pos: Vec<(i64,i64)> = rock
+            .iter()
+            .map(|coord| {
+                (coord.0 as i64 + (highest_rock + 4) as i64, coord.1 as i64 + 2)
+            })
+            .collect();
+        Rock { pos }
+    }
+
+    pub fn right(&self) -> Self {
+        for coord in self.pos.iter() {
+            if coord.1 >= (WIDTH-1) as i64 {
+                return self.clone()
+            }
+        }
+        Rock {
+            pos: self.pos.iter().map(|coord| {
+                (coord.0, coord.1 + 1) // move right, only check for wall !
+            }).collect()
+        }
+    }
+
+    pub fn left(&self) -> Self {
+        for coord in self.pos.iter() {
+            if coord.1 <= 0 {
+                return self.clone()
+            }
+        }
+        Rock {
+            pos: self.pos.iter().map(|coord| {
+                (coord.0, coord.1 - 1) // move left, only check for wall !
+            }).collect()
+        }
+    }
+
+    pub fn down(&self) -> Self {
+        Rock {
+            pos: self.pos.iter().map(|coord| {
+                (coord.0 - 1, coord.1) // move down
+            }).collect()
+        }
+    }
+
+    pub fn valid_pos(&self, chamber: &Vec<Vec<bool>>) -> bool {
+        for coord in &self.pos {
+            if coord.0 < 0 || coord.1 < 0 {
+                return false
+            }
+            if chamber[coord.0 as usize][coord.1 as usize] {
+                return false
+            }
+        }
+
+        true
+    }
+}