Day 8, Day9p1, updated solve_day macro

advent_of_code_2024/src/day8/part1.rs

@@ -1,3 +1,55 @@
-pub fn solve(input: &str) {
+use std::collections::{HashMap, HashSet};
 
+#[allow(unused)]
+fn draw_antinodes(grid: &[&str], antinodes: &HashSet<(i64, i64)>) {
+    for (ypos, line) in grid.iter().enumerate() {
+        for (xpos, ch) in line.as_bytes().iter().enumerate() {
+            if antinodes.contains(&(xpos as i64, ypos as i64)) {
+                print!("#");
+            } else {
+                print!("{}", *ch as char);
+            }
+        }
+        println!();
+    }
+}
+
+fn is_valid_node(width: i64, height: i64, node: (i64, i64)) -> bool{
+    node.0 >= 0 && node.0 < width && node.1 >= 0 && node.1 < height
+}
+
+pub fn solve(input: &str) {
+    let lines = input.lines().collect::<Vec<_>>();
+    let height = lines.len() as i64;
+    let width = lines[0].len() as i64;
+
+    let mut antennas: HashMap<u8, Vec<(i64, i64)>> = HashMap::new();
+
+    for (ypos, line) in lines.iter().enumerate() {
+        for (xpos, object) in line.as_bytes().iter().enumerate() {
+            if *object != b'.' {
+                antennas.entry(*object).or_default().push((xpos as i64, ypos as i64));
+            }
+        }
+    }
+
+    let mut antinodes: HashSet<(i64, i64)> = HashSet::new();
+
+    for (_, antennas) in antennas.iter() {
+        for (idx, first) in antennas.iter().enumerate() {
+            for second in &antennas[(idx + 1)..] {
+                let dx = second.0 - first.0;
+                let dy = second.1 - first.1;
+                
+                if is_valid_node(width, height, (second.0 + dx, second.1 + dy)) {
+                    antinodes.insert((second.0 + dx, second.1 + dy));
+                }
+                if is_valid_node(width, height, (first.0 - dx, first.1 - dy)) {
+                    antinodes.insert((first.0 - dx, first.1 - dy));
+                }
+            }
+        }
+    }
+
+    println!("# antinodes: {}", antinodes.len());
 }

advent_of_code_2024/src/day8/part2.rs

@@ -1,4 +1,70 @@
+use std::collections::{HashMap, HashSet};
+
+#[allow(unused)]
+fn draw_antinodes(grid: &[&str], antinodes: &HashSet<(i64, i64)>) {
+    for (ypos, line) in grid.iter().enumerate() {
+        for (xpos, ch) in line.as_bytes().iter().enumerate() {
+            if antinodes.contains(&(xpos as i64, ypos as i64)) {
+                print!("#");
+            } else {
+                print!("{}", *ch as char);
+            }
+        }
+        println!();
+    }
+}
+
+fn is_valid_node(width: i64, height: i64, node: (i64, i64)) -> bool{
+    node.0 >= 0 && node.0 < width && node.1 >= 0 && node.1 < height
+}
+
+fn calculate_node(start: &(i64, i64), delta: (i64, i64), step: i64) -> (i64, i64) {
+    (start.0 + delta.0 * step, start.1 + delta.1 * step)
+}
 
 pub fn solve(input: &str) {
+    let lines = input.lines().collect::<Vec<_>>();
+    let height = lines.len() as i64;
+    let width = lines[0].len() as i64;
 
+    let mut antennas: HashMap<u8, Vec<(i64, i64)>> = HashMap::new();
+
+    for (ypos, line) in lines.iter().enumerate() {
+        for (xpos, object) in line.as_bytes().iter().enumerate() {
+            if *object != b'.' {
+                antennas.entry(*object).or_default().push((xpos as i64, ypos as i64));
+            }
+        }
+    }
+
+    let mut antinodes: HashSet<(i64, i64)> = HashSet::new();
+
+    for (_, antennas) in antennas.iter() {
+        for (idx, first) in antennas.iter().enumerate() {
+            for second in &antennas[(idx + 1)..] {
+                let dx = second.0 - first.0;
+                let dy = second.1 - first.1;
+                
+                for idx in 0i64.. {
+                    let node = calculate_node(second, (dx, dy), idx);
+                    if is_valid_node(width, height, node) {
+                        antinodes.insert(node);
+                    } else {
+                        break;
+                    }
+                }
+
+                for idx in 0.. {
+                    let node = calculate_node(first, (dx, dy), -idx);
+                    if is_valid_node(width, height, node) {
+                        antinodes.insert(node);
+                    } else {
+                        break;
+                    }
+                }
+            }
+        }
+    }
+
+    println!("# antinodes: {}", antinodes.len());
 }

advent_of_code_2024/src/day8/test.txt

@@ -0,0 +1,12 @@
+............
+........0...
+.....0......
+.......0....
+....0.......
+......A.....
+............
+............
+........A...
+.........A..
+............
+............

advent_of_code_2024/src/day8/test2.txt

@@ -0,0 +1,7 @@
+b.....a
+.......
+.......
+c.....c
+.......
+.......
+a.....b

advent_of_code_2024/src/day9/part1.rs

@@ -1,3 +1,76 @@
-pub fn solve(input: &str) {
+type Block = Option<u64>;
 
+fn print_uncompressed(fs: &[Block]) {
+    for (idx, block) in fs.iter().enumerate() {
+        match block {
+            Some(num) => print!("{}", num),
+            None => print!("."),
+        }
+    }
+    println!();
+}
+
+fn find_empty(fs: &[Block], start: usize) -> usize {
+    for (idx, block) in fs.iter().enumerate().skip(start) {
+        if block.is_none() {
+            return idx;
+        }
+    }
+
+    fs.len()
+}
+
+fn find_last_block(fs: &[Block], start: usize) -> usize {
+    for offset in 0usize.. {
+        let idx = start - offset;
+        if fs[idx].is_some() {
+            return idx;
+        }
+    }
+
+    0
+}
+
+pub fn solve(input: &str) {
+    let compressed = input.as_bytes();
+    let mut uncompressed: Vec<Block> = Vec::new();
+
+    let mut file_id = 0u64;
+    for (idx, byte) in compressed.iter().enumerate() {
+        let number = (byte - b'0') as usize;
+        if idx % 2 == 1 {
+            // free space
+            for _ in 0..number {
+                uncompressed.push(None);
+            }
+        } else {
+            for _ in 0..number {
+                uncompressed.push(Some(file_id));
+            }
+            file_id += 1;
+        }
+    }
+    
+    let mut free_block = find_empty(&uncompressed, 0);
+    let mut last_block = find_last_block(&uncompressed, uncompressed.len() - 1);
+    // print!("len: {}, free: {:0>2}, last: {:0>2} - ", uncompressed.len(), free_block, last_block);
+    // print_uncompressed(&uncompressed);
+
+    while free_block < last_block {
+        uncompressed[free_block] = uncompressed[last_block];
+        uncompressed[last_block] = None;
+
+        free_block = find_empty(&uncompressed, free_block);
+        last_block = find_last_block(&uncompressed, last_block);
+    }
+
+    let mut checksum: u64 = 0;
+    for (idx, block) in uncompressed.iter().enumerate() {
+        match block {
+            Some(num) => checksum += num * (idx as u64),
+            None => break,
+        }
+    }
+
+    println!("Filesystem checksum: {}", checksum);
 }

advent_of_code_2024/src/day9/test.txt

@@ -0,0 +1 @@
+2333133121414131402

advent_of_code_2024/src/main.rs

@@ -1,22 +1,4 @@
 use paste::paste;
-
-mod day1;
-mod day2;
-mod day3;
-mod day4;
-mod day5;
-mod day6;
-mod day7;
-mod day8;
-mod day9;
 mod utility;
 
-pub fn main() {
-    solve_day!(1);
-    solve_day!(2);
-    solve_day!(3);
-    solve_day!(4);
-    solve_day!(5);
-    solve_day!(6);
-    solve_day!(7);
-}
+solve_day!(8);

advent_of_code_2024/src/utility/solveday.rs

@@ -1,26 +1,30 @@
-
 #[macro_export]
 macro_rules! solve_day {
-    ( $day:literal ) => {{
-        println!("-- Day {} --", $day);
-        let input = utility::get_input_string($day);
-        paste!{ [<day $day>] ::part1::solve(&input) };
-        paste!{ [<day $day>] ::part2::solve(&input) };
-    }}
+    ($day:literal) => {
+        paste! {mod  [<day $day>];}
+
+        pub fn main() {
+            println!("-- Day {} --", $day);
+            let input = utility::get_input_string($day);
+            paste! { [<day $day>] ::part1::solve(&input) };
+            paste! { [<day $day>] ::part2::solve(&input) };
+        }
+    };
+    ($day:literal, $filename:literal) => {
+        paste! {mod  [<day $day>];}
+
+        pub fn main() {
+            println!("-- Day {} --", $day);
+            let input = utility::get_test_string($day, Some($filename));
+            paste! { [<day $day>] ::part1::solve(&input) };
+            paste! { [<day $day>] ::part2::solve(&input) };
+        }
+    };
 }
 
 #[macro_export]
 macro_rules! test_day {
-    ( $day:literal ) => {{
-        println!("-- Day {} --", $day);
-        let input = utility::get_test_string($day, None);
-        paste!{ [<day $day>] ::part1::solve(&input) };
-        paste!{ [<day $day>] ::part2::solve(&input) };
-    }};
-    ( $day:literal, $filename:literal ) => {{
-        println!("-- Day {} --", $day);
-        let input = utility::get_test_string($day, Some($filename));
-        paste!{ [<day $day>] ::part1::solve(&input) };
-        paste!{ [<day $day>] ::part2::solve(&input) };
-    }}
+    ($day:literal) => {
+        solve_day!($day, "test.txt");
+    };
 }