d16-None; d17-P1; d18-P1&P2

d18/src/a2.rs

@@ -1,5 +1,149 @@
+use std::{collections::{HashSet, VecDeque, vec_deque}, hash::Hash, thread};
 
 
+#[derive(Hash, PartialEq, Eq, Copy, Clone)]
+struct Pos {
+    x: i32,
+    y: i32,
+    z: i32, 
+}
+
+impl Pos {
+    fn from(x :i32, y :i32, z :i32) -> Self {
+        Pos { x: x, y: y, z: z }
+    }
+
+
+}
+
+fn find_zmax(positions :&HashSet<Pos>) -> Pos {
+    let mut max = Pos::from(0, 0, i32::MIN); 
+    positions.iter().for_each(|pos| {if pos.z > max.z { max = *pos; }}); 
+    max
+}
+
+fn find_zmin(positions :&HashSet<Pos>) -> Pos {
+    let mut max = Pos::from(0, 0, i32::MAX); 
+    positions.iter().for_each(|pos| {if pos.z < max.z { max = *pos; }}); 
+    max
+}
+
+fn find_ymax(positions :&HashSet<Pos>) -> Pos {
+    let mut max = Pos::from(0, i32::MIN, 0); 
+    positions.iter().for_each(|pos| {if pos.y > max.y { max = *pos; }}); 
+    max
+}
+
+fn find_ymin(positions :&HashSet<Pos>) -> Pos {
+    let mut max = Pos::from(0, i32::MAX, 0); 
+    positions.iter().for_each(|pos| {if pos.y < max.y { max = *pos; }}); 
+    max
+}
+
+fn find_xmax(positions :&HashSet<Pos>) -> Pos {
+    let mut max = Pos::from(i32::MIN, 0, 0); 
+    positions.iter().for_each(|pos| {if pos.x > max.x { max = *pos; }}); 
+    max
+}
+
+fn find_xmin(positions :&HashSet<Pos>) -> Pos {
+    let mut max = Pos::from(i32::MAX, 0, 0); 
+    positions.iter().for_each(|pos| {if pos.x < max.x { max = *pos; }}); 
+    max
+}
+
+fn flood_fill(start :Pos, map :&mut HashSet<Pos>, lava :&HashSet<Pos>, min :&Pos, max :&Pos) {
+
+    let mut queue :VecDeque<Pos> = VecDeque::new();
+    queue.push_back(start);  
+
+    while !queue.is_empty() {
+
+        let cp = queue.pop_front().unwrap(); 
+    
+        if !(cp.x > min.x && cp.x < max.x && cp.y > min.y && cp.y < max.y && cp.z > min.z && cp.z < max.z) {
+            continue; 
+        }
+    
+        if map.contains(&cp) {
+            continue;
+        }
+    
+        if lava.contains(&cp) {
+            continue;
+        }
+    
+        map.insert(cp); 
+    
+        queue.push_back(Pos::from(cp.x - 1, cp.y, cp.z)); 
+        queue.push_back(Pos::from(cp.x + 1, cp.y, cp.z)); 
+        queue.push_back(Pos::from(cp.x, cp.y - 1, cp.z)); 
+        queue.push_back(Pos::from(cp.x, cp.y + 1, cp.z)); 
+        queue.push_back(Pos::from(cp.x, cp.y, cp.z - 1)); 
+        queue.push_back(Pos::from(cp.x, cp.y, cp.z + 1)); 
+
+    }
+}
+
 pub fn run(inp :Vec<String>) {
+
+    // parse input
+    let tmp :Vec<Vec<i32>> = inp.iter().map(|elem| elem.split(',').map(|num| num.parse::<i32>().unwrap()).collect()).collect(); 
+    let droplets :HashSet<Pos> = tmp.iter().map(|drop| Pos::from(drop[0], drop[1], drop[2])).collect(); 
+
+    // highest, lowest, leftmost, rightmost, furthest and nearest droplet 
+    // construct a box around the lava at each sides maximum + 2
+    // floodfill from a starting pooint (for example higest_point+1)
+    // go through all filled pixels and check all 6 sides if there is a pixel 
+
+    // find edges (treat them as WALL)
+    let z_max = find_zmax(&droplets); 
+    let z_min = find_zmin(&droplets); 
+    let y_max = find_ymax(&droplets); 
+    let y_min = find_ymin(&droplets); 
+    let x_max = find_xmax(&droplets); 
+    let x_min = find_xmin(&droplets); 
     
+    let min_edges = Pos::from(x_min.x - 3, y_min.y - 3, z_min.z - 3); 
+    let max_edges = Pos::from(x_max.x + 3, y_max.y + 3, z_max.z + 3); 
+    
+    let mut filled :HashSet<Pos> = HashSet::new(); 
+           
+    // FloodFill the rest in a new HashSet
+    flood_fill(Pos::from(z_max.x, z_max.y, z_max.z+1), &mut filled, &droplets, &min_edges, &max_edges); 
+
+    // check all sides of all flooded pixels. If a side has a LAVA pixel next to it count +1 
+    let mut side_counter = 0; 
+
+    for dp in &filled {
+
+        // check each side if it is free
+        // if it is free then count up by 1
+        // else dont 
+
+        let sides :Vec<Pos> = vec![
+    
+            Pos::from(dp.x-1, dp.y, dp.z),
+            Pos::from(dp.x+1, dp.y, dp.z), 
+    
+            Pos::from(dp.x, dp.y-1, dp.z),
+            Pos::from(dp.x, dp.y+1, dp.z), 
+            
+            Pos::from(dp.x, dp.y, dp.z-1), 
+            Pos::from(dp.x, dp.y, dp.z+1),
+        
+        ]; 
+        
+
+        for side in sides {
+            if droplets.contains(&side) {
+                side_counter += 1; 
+            }
+        }
+
+    }
+
+
+    println!("a2: {}", side_counter); 
+
 }