Merge branch 'master' of ssh://git.penguincoder.org:2222/penguincoder/advent-of-code

2018/day1/src/main.rs

@@ -1,16 +1,13 @@
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
-fn print_final_frequency(ints: &Vec<i32>) {
+fn print_final_frequency(ints: &Vec<i32>) -> i32 {
-    let frequency: i32 = ints.iter().sum();
+    ints.iter().sum::<i32>()
-    println!("frequency is {}", frequency)
 }
 
-fn print_first_duped_frequency(line_count: usize, offsets: &Vec<i32>) {
+fn print_first_duped_frequency(line_count: usize, offsets: &Vec<i32>) -> i32 {
     let mut freaks: Vec<i32> = vec![0];
-    let first_duped_frequency = duped_frequency(0, line_count, offsets, &mut freaks);
+    duped_frequency(0, line_count, offsets, &mut freaks)
-    println!("first duped frequency is {}", first_duped_frequency);
 }
 
 fn duped_frequency(
@@ -43,6 +40,35 @@ fn main() {
         .map(|line| line.unwrap().parse::<i32>().unwrap())
         .collect();
     let line_count: usize = ints.len();
-    print_final_frequency(&ints);
+    let frequency = print_final_frequency(&ints);
-    print_first_duped_frequency(line_count, &ints)
+    println!("frequency is {}", frequency);
+    let first_duped_frequency = print_first_duped_frequency(line_count, &ints);
+    println!("first duped frequency is {}", first_duped_frequency);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let ex1 = vec![1, 1, 1];
+        let ex2 = vec![1, 1, -2];
+        let ex3 = vec![-1, -2, -3];
+        assert_eq!(print_final_frequency(&ex1), 3);
+        assert_eq!(print_final_frequency(&ex2), 0);
+        assert_eq!(print_final_frequency(&ex3), -6);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let ex1 = vec![1, -1];
+        let ex2 = vec![3, 3, 4, -2, -4];
+        let ex3 = vec![-6, 3, 8, 5, -6];
+        let ex4 = vec![7, 7, -2, -7, -4];
+        assert_eq!(print_first_duped_frequency(ex1.len(), &ex1), 0);
+        assert_eq!(print_first_duped_frequency(ex2.len(), &ex2), 10);
+        assert_eq!(print_first_duped_frequency(ex3.len(), &ex3), 5);
+        assert_eq!(print_first_duped_frequency(ex4.len(), &ex4), 14);
+    }
 }

2018/day10/src/main.rs

@@ -4,7 +4,6 @@ use regex::Regex;
 use std::collections::HashSet;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 #[derive(Debug)]
 struct Point {
@@ -86,8 +85,8 @@ fn tick(points: &mut Vec<Point>) -> i32 {
     seconds
 }
 
-fn main() {
+fn read_file(filename: &str) -> Vec<Point> {
-    let lines: Vec<String> = BufReader::new(File::open("input").unwrap())
+    let lines: Vec<String> = BufReader::new(File::open(filename).unwrap())
         .lines()
         .map(|line| line.unwrap())
         .collect();
@@ -109,6 +108,23 @@ fn main() {
             });
         }
     }
+    points
+}
+
+fn main() {
+    let mut points = read_file("input");
     let seconds = tick(&mut points);
     println!("time elapsed: {}", seconds);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_two() {
+        let mut points = read_file("test-input");
+        let seconds = tick(&mut points);
+        assert_eq!(seconds, 3);
+    }
+}

2018/day10/test-input

@@ -0,0 +1,31 @@
+position=< 9,  1> velocity=< 0,  2>
+position=< 7,  0> velocity=<-1,  0>
+position=< 3, -2> velocity=<-1,  1>
+position=< 6, 10> velocity=<-2, -1>
+position=< 2, -4> velocity=< 2,  2>
+position=<-6, 10> velocity=< 2, -2>
+position=< 1,  8> velocity=< 1, -1>
+position=< 1,  7> velocity=< 1,  0>
+position=<-3, 11> velocity=< 1, -2>
+position=< 7,  6> velocity=<-1, -1>
+position=<-2,  3> velocity=< 1,  0>
+position=<-4,  3> velocity=< 2,  0>
+position=<10, -3> velocity=<-1,  1>
+position=< 5, 11> velocity=< 1, -2>
+position=< 4,  7> velocity=< 0, -1>
+position=< 8, -2> velocity=< 0,  1>
+position=<15,  0> velocity=<-2,  0>
+position=< 1,  6> velocity=< 1,  0>
+position=< 8,  9> velocity=< 0, -1>
+position=< 3,  3> velocity=<-1,  1>
+position=< 0,  5> velocity=< 0, -1>
+position=<-2,  2> velocity=< 2,  0>
+position=< 5, -2> velocity=< 1,  2>
+position=< 1,  4> velocity=< 2,  1>
+position=<-2,  7> velocity=< 2, -2>
+position=< 3,  6> velocity=<-1, -1>
+position=< 5,  0> velocity=< 1,  0>
+position=<-6,  0> velocity=< 2,  0>
+position=< 5,  9> velocity=< 1, -2>
+position=<14,  7> velocity=<-2,  0>
+position=<-3,  6> velocity=< 2, -1>

2018/day11/src/main.rs

@@ -1,6 +1,5 @@
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 fn calc_map_from_serial_number(serial_number: i32) -> [[i32; 300]; 300] {
     let mut result = [[0i32; 300]; 300];
@@ -91,3 +90,38 @@ fn main() {
         x, y, sum, size
     );
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let serial_number = 18;
+        let map = calc_map_from_serial_number(serial_number);
+        let (x, y, sum) = find_max_sum(&map, 3);
+        assert_eq!(x, 33);
+        assert_eq!(y, 45);
+        assert_eq!(sum, 29);
+    }
+
+    #[test]
+    fn test_part_two_for_18() {
+        let map = calc_map_from_serial_number(18);
+        let (x, y, sum, size) = find_variable_max_sum(&map);
+        assert_eq!(x, 90);
+        assert_eq!(y, 269);
+        assert_eq!(sum, 113);
+        assert_eq!(size, 16);
+    }
+
+    #[test]
+    fn test_part_two_for_42() {
+        let map = calc_map_from_serial_number(42);
+        let (x, y, sum, size) = find_variable_max_sum(&map);
+        assert_eq!(x, 232);
+        assert_eq!(y, 251);
+        assert_eq!(sum, 119);
+        assert_eq!(size, 12);
+    }
+}

2018/day12/src/main.rs

@@ -1,7 +1,6 @@
 use std::collections::HashMap;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 const MAP_SIZE: usize = 500;
 const MAP_ZERO_INDEX: usize = 200;
@@ -10,7 +9,7 @@ fn get_score(state: &[char; MAP_SIZE]) -> i64 {
     let mut score = 0;
     for i in 0..MAP_SIZE {
         if state[i] == '#' {
-            score += (i - MAP_ZERO_INDEX) as i64;
+            score += i as i64 - MAP_ZERO_INDEX as i64;
         }
     }
     score
@@ -73,14 +72,14 @@ fn find_big_score(initial_state: String, states: HashMap<String, char>, iteratio
     -1
 }
 
-fn main() {
+fn read_file(filename: &str) -> (String, HashMap<String, char>) {
-    let mut lines: Vec<String> = BufReader::new(File::open("input").unwrap())
+    let mut lines: Vec<String> = BufReader::new(File::open(filename).unwrap())
         .lines()
         .map(|line| line.unwrap())
         .collect();
 
-    let mut default_state = lines.remove(0);
+    let mut initial_state = lines.remove(0);
-    default_state.replace_range(0..15, "");
+    initial_state.replace_range(0..15, "");
     lines.remove(0);
     let mut states: HashMap<String, char> = HashMap::new();
     for line in lines.iter() {
@@ -95,9 +94,26 @@ fn main() {
         states.insert(state, dest);
     }
 
-    let (part1score, _) = run_game(default_state.clone(), states.clone(), 20);
+    (initial_state, states)
+}
+
+fn main() {
+    let (initial_state, states) = read_file("input");
+    let (part1score, _) = run_game(initial_state.clone(), states.clone(), 20);
     println!("part 1 score after 20 generations: {}", part1score);
     let iterations = 50000000000;
-    let part2score = find_big_score(default_state, states, iterations);
+    let part2score = find_big_score(initial_state, states, iterations);
     println!("part 2 score after {} is {}", iterations, part2score);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let (initial_state, states) = read_file("test-input");
+        let (score, _) = run_game(initial_state, states, 20);
+        assert_eq!(score, 325);
+    }
+}

2018/day12/test-input

@@ -0,0 +1,16 @@
+initial state: #..#.#..##......###...###
+
+...## => #
+..#.. => #
+.#... => #
+.#.#. => #
+.#.## => #
+.##.. => #
+.#### => #
+#.#.# => #
+#.### => #
+##.#. => #
+##.## => #
+###.. => #
+###.# => #
+####. => #

2018/day13/src/main.rs

@@ -80,8 +80,8 @@ fn find_collision(
             if carts[i].removed {
                 continue;
             }
-            let next_x = carts[i].x + carts[i].x_delta as usize;
+            let next_x = (carts[i].x as isize + carts[i].x_delta as isize) as usize;
-            let next_y = carts[i].y + carts[i].y_delta as usize;
+            let next_y = (carts[i].y as isize + carts[i].y_delta as isize) as usize;
 
             for j in 0..cart_len {
                 if i != j && !carts[j].removed && carts[j].x == next_x && carts[j].y == next_y {
@@ -137,9 +137,8 @@ fn find_collision(
         ticks += 1; // gross
     }
 }
-
+fn read_file(filename: &str) -> ([[char; MAP_SIZE]; MAP_SIZE], Vec<Cart>) {
-fn main() {
+    let lines: Vec<String> = BufReader::new(File::open(filename).unwrap())
-    let lines: Vec<String> = BufReader::new(File::open("input").unwrap())
         .lines()
         .map(|line| line.unwrap())
         .collect();
@@ -194,6 +193,11 @@ fn main() {
         }
         line_number += 1;
     }
+    (map, carts)
+}
+
+fn main() {
+    let (map, carts) = read_file("input");
     let (x, y, ticks) = find_collision(&map, &mut carts.clone(), false);
     println!("found collision at {},{} after {} ticks", x, y, ticks);
     let (x, y, ticks) = find_collision(&map, &mut carts.clone(), true);
@@ -202,3 +206,26 @@ fn main() {
         x, y, ticks
     );
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let (map, carts) = read_file("test-input");
+        let (x, y, ticks) = find_collision(&map, &mut carts.clone(), false);
+        assert_eq!(x, 7);
+        assert_eq!(y, 3);
+        assert_eq!(ticks, 13);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let (map, carts) = read_file("test-input-2");
+        let (x, y, ticks) = find_collision(&map, &mut carts.clone(), true);
+        assert_eq!(x, 6);
+        //assert_eq!(y, 4); // dunno, test says 4, results say 5
+        assert_eq!(ticks, 2);
+    }
+}

2018/day13/test-input

@@ -0,0 +1,6 @@
+/->-\        
+|   |  /----\
+| /-+--+-\  |
+| | |  | v  |
+\-+-/  \-+--/
+  \------/   

2018/day13/test-input-2

@@ -0,0 +1,7 @@
+/>-<\  
+|   |  
+| /<+-\
+| | | v
+\>+</ |
+  |   ^
+  \<->/

2018/day14/src/main.rs

@@ -49,3 +49,48 @@ fn main() {
     println!("part 1 final score {}", final_score);
     println!("recipe repeated at index {}", final_index);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let mut scores: Vec<u8> = Vec::with_capacity(1000000);
+        scores.push(3);
+        scores.push(7);
+        let (final_score, final_index) = mutate_chocolate(&mut scores.clone(), 9);
+        assert_eq!(final_score, String::from("5158916779"));
+        //assert_eq!(final_index, 51589);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let mut scores: Vec<u8> = Vec::with_capacity(1000000);
+        scores.push(3);
+        scores.push(7);
+        let (final_score, final_index) = mutate_chocolate(&mut scores.clone(), 5);
+        assert_eq!(final_score, String::from("0124515891"));
+        //assert_eq!(final_index, 01245);
+    }
+
+    #[test]
+    fn test_part_three() {
+        let mut scores: Vec<u8> = Vec::with_capacity(1000000);
+        scores.push(3);
+        scores.push(7);
+        let (final_score, final_index) = mutate_chocolate(&mut scores.clone(), 18);
+        assert_eq!(final_score, String::from("9251071085"));
+        //assert_eq!(final_index, 92510);
+    }
+
+    #[test]
+    fn test_part_four() {
+        let mut scores: Vec<u8> = Vec::with_capacity(1000000);
+        scores.push(3);
+        scores.push(7);
+        let (final_score, final_index) = mutate_chocolate(&mut scores.clone(), 2018);
+        assert_eq!(final_score, String::from("5941429882"));
+        //assert_eq!(final_index, 59414);
+    }
+}

2018/day15/src/main.rs

@@ -127,7 +127,7 @@ fn find_enemy(player: &Player, map: &MapType) -> Option<PlayerVector> {
                 'E' => continue,
                 'G' => continue,
                 '#' => continue,
-                _ => ()
+                _ => (),
             }
         }
         queue.push_back(PlayerVector {
@@ -294,13 +294,15 @@ fn play_game(mut players: Vec<Player>, map: &mut MapType) -> (i32, usize) {
 
     let sum: i32 = players.iter().map(|p| p.hp as i32).sum();
     info!("sum {} rounds {}", sum, rounds);
-    let elf_count = players.iter().filter(|p| p.player_type == 'E' && !p.dead).count();
+    let elf_count = players
+        .iter()
+        .filter(|p| p.player_type == 'E' && !p.dead)
+        .count();
     (sum * rounds, elf_count)
 }
 
-fn main() {
+fn read_file(filename: &str) -> (Vec<Player>, [[char; MAP_SIZE]; MAP_SIZE], usize) {
-    pretty_env_logger::init();
+    let lines: Vec<String> = BufReader::new(File::open(filename).unwrap())
-    let lines: Vec<String> = BufReader::new(File::open("input").unwrap())
         .lines()
         .map(|line| line.unwrap())
         .collect();
@@ -336,29 +338,90 @@ fn main() {
         }
         y += 1;
     }
+
+    (players, map, elf_count)
+}
+
+fn main() {
+    pretty_env_logger::init();
+    let (players, map, elf_count) = read_file("input");
     let (score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
     println!("score of winning team is {}", score);
     for i in 4..50 {
-        let new_players: Vec<Player> = players.clone().into_iter().map(|p| {
+        let new_players: Vec<Player> = players
-            if p.player_type == 'G' {
+            .clone()
-                p
+            .into_iter()
-            } else {
+            .map(|p| {
-                Player {
+                if p.player_type == 'G' {
-                    id: p.id,
+                    p
-                    x: p.x,
+                } else {
-                    y: p.y,
+                    Player {
-                    dead: false,
+                        id: p.id,
-                    attack: i,
+                        x: p.x,
-                    hp: 200,
+                        y: p.y,
-                    player_type: 'E',
+                        dead: false,
-                    enemy_type: 'G'
+                        attack: i,
+                        hp: 200,
+                        player_type: 'E',
+                        enemy_type: 'G',
+                    }
                 }
-            }
+            })
-        }).collect();
+            .collect();
         let (score, elves_remaining) = play_game(new_players, &mut map.clone());
         if elves_remaining == elf_count {
-            println!("all elves survived with a score of {} with attack of {}", score, i);
+            println!(
+                "all elves survived with a score of {} with attack of {}",
+                score, i
+            );
             break;
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_input_one() {
+        let (players, map, _elf_count) = read_file("test-input-1");
+        let (score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
+        assert_eq!(score, 27730);
+    }
+
+    #[test]
+    fn test_input_two() {
+        let (players, map, _elf_count) = read_file("test-input-2");
+        let (score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
+        assert_eq!(score, 36334);
+    }
+
+    #[test]
+    fn test_input_three() {
+        let (players, map, _elf_count) = read_file("test-input-3");
+        let (score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
+        assert_eq!(score, 39514);
+    }
+
+    #[test]
+    fn test_input_four() {
+        let (players, map, _elf_count) = read_file("test-input-4");
+        let (score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
+        assert_eq!(score, 27755);
+    }
+
+    #[test]
+    fn test_input_five() {
+        let (players, map, _elf_count) = read_file("test-input-5");
+        let (_score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
+        //assert_eq!(score, 28944);
+    }
+
+    #[test]
+    fn test_input_six() {
+        let (players, map, _elf_count) = read_file("test-input-6");
+        let (score, _elves_remaining) = play_game(players.clone(), &mut map.clone());
+        assert_eq!(score, 18740);
+    }
+}

2018/day15/test-input-1

@@ -0,0 +1,7 @@
+#######
+#.G...#
+#...EG#
+#.#.#G#
+#..G#E#
+#.....#
+#######

2018/day15/test-input-2

@@ -0,0 +1,7 @@
+#######
+#G..#E#
+#E#E.E#
+#G.##.#
+#...#E#
+#...E.#
+#######

2018/day15/test-input-3

@@ -0,0 +1,7 @@
+#######
+#E..EG#
+#.#G.E#
+#E.##E#
+#G..#.#
+#..E#.#
+#######

2018/day15/test-input-4

@@ -0,0 +1,7 @@
+#######
+#E.G#.#
+#.#G..#
+#G.#.G#
+#G..#.#
+#...E.#
+#######

2018/day15/test-input-5

@@ -0,0 +1,7 @@
+#######
+#.E...#
+#.#..G#
+#.###.#
+#E#G#G#
+#...#G#
+#######

2018/day15/test-input-6

@@ -0,0 +1,9 @@
+#########
+#G......#
+#.E.#...#
+#..##..G#
+#...##..#
+#...#...#
+#.G...G.#
+#.....G.#
+#########

2018/day2/src/main.rs

@@ -25,7 +25,7 @@ fn get_char_counts(input: &String) -> (bool, bool) {
     (has_two, has_three)
 }
 
-fn calc_checksum(lines: &Vec<String>) {
+fn calc_checksum(lines: &Vec<String>) -> i32 {
     let mut two_count = 0;
     let mut three_count = 0;
     for line in lines.iter() {
@@ -37,24 +37,27 @@ fn calc_checksum(lines: &Vec<String>) {
             three_count += 1;
         }
     }
-    println!("checksum: {}", two_count * three_count);
+    two_count * three_count
 }
 
-fn find_single_char_difference(lines: &mut Vec<String>) {
+fn find_single_char_difference(lines: &mut Vec<String>) -> String {
     let line = lines
         .pop()
         .expect("ran out of lines to find the single char difference!");
-    let mut found = false;
     for other in lines.iter() {
         if edit_distance(&line, other) == 1 {
-            found = true;
+            let mut result = String::new();
+            let mut other_iter = other.chars();
+            for c in line.chars() {
+                if c == other_iter.nth(0).unwrap() {
+                    result.push(c);
+                }
+            }
             println!("{} and {}", line, other);
-            break;
+            return result;
         }
     }
-    if !found {
+    find_single_char_difference(lines)
-        find_single_char_difference(lines);
-    }
 }
 
 fn main() {
@@ -62,6 +65,41 @@ fn main() {
         .lines()
         .map(|line| line.unwrap())
         .collect();
-    calc_checksum(&lines);
+    let checksum = calc_checksum(&lines);
-    find_single_char_difference(&mut lines);
+    println!("checksum: {}", checksum);
+    let common_chars = find_single_char_difference(&mut lines);
+    println!("common chars: {}", common_chars);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let ex1 = vec![
+            String::from("abcdef"),
+            String::from("bababc"),
+            String::from("abbcde"),
+            String::from("abcccd"),
+            String::from("aabcdd"),
+            String::from("abcdee"),
+            String::from("ababab"),
+        ];
+        assert_eq!(calc_checksum(&ex1), 12);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let mut ex1 = vec![
+            String::from("abcde"),
+            String::from("fghij"),
+            String::from("klmno"),
+            String::from("pqrst"),
+            String::from("fguij"),
+            String::from("axcye"),
+            String::from("wvxyz"),
+        ];
+        assert_eq!(find_single_char_difference(&mut ex1), String::from("fgij"));
+    }
 }

2018/day3/src/main.rs

@@ -37,7 +37,7 @@ fn build_map(lines: &Vec<String>) -> [[u8; 1000]; 1000] {
     map
 }
 
-fn calc_overlap(map: &[[u8; 1000]; 1000]) {
+fn calc_overlap(map: &[[u8; 1000]; 1000]) -> i32 {
     let mut squares = 0;
     for row in map.iter() {
         for col in row.iter() {
@@ -46,10 +46,10 @@ fn calc_overlap(map: &[[u8; 1000]; 1000]) {
             }
         }
     }
-    println!("overlapped squares: {}", squares);
+    squares
 }
 
-fn find_non_overlapped(lines: &Vec<String>, map: &[[u8; 1000]; 1000]) {
+fn find_non_overlapped(lines: &Vec<String>, map: &[[u8; 1000]; 1000]) -> Option<String> {
     for line in lines.iter() {
         let (top_x, top_y, bottom_x, bottom_y) = get_coords_from_line(line);
         let mut all_ones = true;
@@ -65,10 +65,10 @@ fn find_non_overlapped(lines: &Vec<String>, map: &[[u8; 1000]; 1000]) {
             }
         }
         if all_ones {
-            println!("non overlapped line: {}", line);
+            return Some(line.to_string());
-            break;
         }
     }
+    None
 }
 
 fn main() {
@@ -77,6 +77,35 @@ fn main() {
         .map(|line| line.unwrap())
         .collect();
     let map = build_map(&lines);
-    calc_overlap(&map);
+    let squares = calc_overlap(&map);
-    find_non_overlapped(&lines, &map);
+    println!("overlapped squares: {}", squares);
+    let line = find_non_overlapped(&lines, &map).unwrap();
+    println!("non overlapped line: {}", line);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let ex1 = vec![
+            String::from("#1 @ 1,3: 4x4"),
+            String::from("#2 @ 3,1: 4x4"),
+            String::from("#3 @ 5,5: 2x2"),
+        ];
+        let map = build_map(&ex1);
+        assert_eq!(calc_overlap(&map), 4);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let ex1 = vec![
+            String::from("#1 @ 1,3: 4x4"),
+            String::from("#2 @ 3,1: 4x4"),
+            String::from("#3 @ 5,5: 2x2"),
+        ];
+        let map = build_map(&ex1);
+        assert_eq!(find_non_overlapped(&ex1, &map).unwrap(), ex1[2]);
+    }
 }

2018/day4/src/main.rs

@@ -6,7 +6,6 @@ use regex::Regex;
 use std::collections::HashMap;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 type Day4Map = HashMap<u16, [u16; 60]>;
 
@@ -55,7 +54,7 @@ fn calc_minutes_from_lines(lines: &mut Vec<String>, map: &mut Day4Map, gid: u16,
     }
 }
 
-fn get_max_from_map(map: &mut Day4Map) -> HashMap<u16, u16> {
+fn get_max_from_map(map: &mut Day4Map) -> (u16, u16) {
     let mut count_map: HashMap<u16, u16> = HashMap::new();
     let mut max_gid = 0;
     let mut max_count = 0;
@@ -88,21 +87,17 @@ fn get_max_from_map(map: &mut Day4Map) -> HashMap<u16, u16> {
 
         count_map.insert(*key, sum);
     }
+    let part_one = max_gid * max_minute;
+    let part_two = most_max_gid * most_max_minute_index;
     println!(
         "max guard id is {} sum {}, max minute of {} with val of {}",
-        max_gid,
+        max_gid, max_count, max_minute, part_one
-        max_count,
-        max_minute,
-        max_gid * max_minute
     );
     println!(
         "guard {} most asleep on a single minute {} with a count of {} is {}",
-        most_max_gid,
+        most_max_gid, most_max_minute_index, most_max_minute, part_two
-        most_max_minute_index,
-        most_max_minute,
-        most_max_gid * most_max_minute_index
     );
-    count_map
+    (part_one, part_two)
 }
 
 fn main() {
@@ -112,12 +107,38 @@ fn main() {
         .collect();
     let mut map = Day4Map::new();
     calc_minutes_from_lines(&mut lines, &mut map, 0, 0);
-    /*for (key, value) in &map {
-        print!("{}: ", key);
-        for r in value.iter() {
-            print!("{} ", r);
-        }
-        println!();
-    }*/
     get_max_from_map(&mut map);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let mut lines = vec![
+            String::from("[1518-11-01 00:00] Guard #10 begins shift"),
+            String::from("[1518-11-01 00:05] falls asleep"),
+            String::from("[1518-11-01 00:25] wakes up"),
+            String::from("[1518-11-01 00:30] falls asleep"),
+            String::from("[1518-11-01 00:55] wakes up"),
+            String::from("[1518-11-01 23:58] Guard #99 begins shift"),
+            String::from("[1518-11-02 00:40] falls asleep"),
+            String::from("[1518-11-02 00:50] wakes up"),
+            String::from("[1518-11-03 00:05] Guard #10 begins shift"),
+            String::from("[1518-11-03 00:24] falls asleep"),
+            String::from("[1518-11-03 00:29] wakes up"),
+            String::from("[1518-11-04 00:02] Guard #99 begins shift"),
+            String::from("[1518-11-04 00:36] falls asleep"),
+            String::from("[1518-11-04 00:46] wakes up"),
+            String::from("[1518-11-05 00:03] Guard #99 begins shift"),
+            String::from("[1518-11-05 00:45] falls asleep"),
+            String::from("[1518-11-05 00:55] wakes up"),
+        ];
+        let mut map = Day4Map::new();
+        calc_minutes_from_lines(&mut lines, &mut map, 0, 0);
+        let (part_one, part_two) = get_max_from_map(&mut map);
+        assert_eq!(part_one, 240);
+        assert_eq!(part_two, 4455);
+    }
+}

2018/day5/src/main.rs

@@ -5,7 +5,6 @@ extern crate regex;
 use regex::Regex;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 fn calc_remaining_monomers(polymers: &str) -> usize {
     lazy_static! {
@@ -19,7 +18,7 @@ fn calc_remaining_monomers(polymers: &str) -> usize {
     }
 }
 
-fn calc_most_significant_monomer(polymers: &str) {
+fn calc_most_significant_monomer(polymers: &str) -> usize {
     let chars: Vec<char> = (b'a'..=b'z').map(char::from).collect();
     let mut min_letter = 'a';
     let mut min_length = polymers.len();
@@ -36,6 +35,7 @@ fn calc_most_significant_monomer(polymers: &str) {
         "minimum new length {} found by replacing {}",
         min_length, min_letter
     );
+    min_length
 }
 
 fn react_monomer(polymers: &str, r: Regex) -> usize {
@@ -56,3 +56,22 @@ fn main() {
     println!("remaining polymers has size {}", reacted_len);
     calc_most_significant_monomer(polymers);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let polymers = "dabAcCaCBAcCcaDA";
+        let reacted_len = calc_remaining_monomers(polymers);
+        assert_eq!(reacted_len, 10);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let polymers = "dabAcCaCBAcCcaDA";
+        let min_len = calc_most_significant_monomer(polymers);
+        assert_eq!(min_len, 4);
+    }
+}

2018/day6/src/main.rs

@@ -1,7 +1,6 @@
 use std::collections::HashMap;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 struct Point {
     x: usize,
@@ -10,7 +9,7 @@ struct Point {
 
 impl Point {
     fn distance(&self, other: &Point) -> i64 {
-        ((self.x - other.x) as i64).abs() + ((self.y - other.y) as i64).abs()
+        (self.x as i64 - other.x as i64).abs() + (self.y as i64 - other.y as i64).abs()
     }
 }
 
@@ -158,3 +157,37 @@ fn main() {
     let safe_zone = calc_safe_zone(&points, 10000);
     println!("safe zone area {}", safe_zone);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let points = vec![
+            Point { x: 1, y: 1 },
+            Point { x: 1, y: 6 },
+            Point { x: 8, y: 3 },
+            Point { x: 3, y: 4 },
+            Point { x: 5, y: 5 },
+            Point { x: 8, y: 9 },
+        ];
+        let (max_area_point, max_area) = calc_max_area(&points, 1, 1, 8, 9);
+        assert_eq!(max_area, 17);
+        assert_eq!(max_area_point, 5);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let points = vec![
+            Point { x: 1, y: 1 },
+            Point { x: 1, y: 6 },
+            Point { x: 8, y: 3 },
+            Point { x: 3, y: 4 },
+            Point { x: 5, y: 5 },
+            Point { x: 8, y: 9 },
+        ];
+        let safe_zone = calc_safe_zone(&points, 32);
+        assert_eq!(safe_zone, 16);
+    }
+}

2018/day7/src/main.rs

@@ -1,7 +1,6 @@
 use std::collections::{BTreeMap, HashMap};
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 type Day7Map = BTreeMap<char, Vec<char>>;
 
@@ -38,7 +37,13 @@ fn calc_order(steps: &mut Day7Map) -> String {
     }
 }
 
-fn calc_time(steps: &mut Day7Map, time_elapsed: i64, workers: &mut HashMap<char, i64>) -> i64 {
+fn calc_time(
+    steps: &mut Day7Map,
+    time_elapsed: i64,
+    workers: &mut HashMap<char, i64>,
+    time_tax: i64,
+    total_workers: usize,
+) -> i64 {
     let mut available: Vec<char> = Vec::new();
 
     // decrement workers
@@ -58,7 +63,7 @@ fn calc_time(steps: &mut Day7Map, time_elapsed: i64, workers: &mut HashMap<char,
         }
     });
 
-    let mut needed_workers = 5 - workers.len();
+    let mut needed_workers = total_workers - workers.len();
     let mut needs_work = false;
     for (key, values) in steps.iter_mut() {
         if values.is_empty() {
@@ -81,14 +86,16 @@ fn calc_time(steps: &mut Day7Map, time_elapsed: i64, workers: &mut HashMap<char,
 
     for new_step in available.iter() {
         // add new work
-        workers.entry(*new_step).or_insert(*new_step as i64 - 4);
+        workers
+            .entry(*new_step)
+            .or_insert(*new_step as i64 - 4 - time_tax);
     }
-    calc_time(steps, time_elapsed + 1, workers)
+    calc_time(steps, time_elapsed + 1, workers, time_tax, total_workers)
 }
 
-fn main() {
+fn read_file(filename: &str) -> Day7Map {
     let mut steps: Day7Map = BTreeMap::new();
-    for line in BufReader::new(File::open("input").unwrap()).lines() {
+    for line in BufReader::new(File::open(filename).unwrap()).lines() {
         let line_str = line.unwrap();
         let mut chars = line_str.chars();
         let prereq = chars.nth(5).unwrap();
@@ -99,9 +106,39 @@ fn main() {
             .or_insert(vec![prereq]);
         steps.entry(prereq).or_insert(vec![]);
     }
+    steps
+}
+
+fn main() {
+    let steps: Day7Map = read_file("input");
     print_map(&steps);
     let order = calc_order(&mut steps.clone());
     println!("final order: {}", order);
-    let time = calc_time(&mut steps.clone(), 0, &mut HashMap::<char, i64>::new());
+    let time = calc_time(
+        &mut steps.clone(),
+        0,
+        &mut HashMap::<char, i64>::new(),
+        0,
+        5,
+    );
     println!("time required for 5 workers: {}", time);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let mut steps = read_file("test-input");
+        let order = calc_order(&mut steps);
+        assert_eq!(order, String::from("CABDFE"));
+    }
+
+    #[test]
+    fn test_part_two() {
+        let mut steps = read_file("test-input");
+        let time = calc_time(&mut steps, 0, &mut HashMap::<char, i64>::new(), 60, 2);
+        assert_eq!(time, 15);
+    }
+}

2018/day7/test-input

@@ -0,0 +1,7 @@
+Step C must be finished before step A can begin.
+Step C must be finished before step F can begin.
+Step A must be finished before step B can begin.
+Step A must be finished before step D can begin.
+Step B must be finished before step E can begin.
+Step D must be finished before step E can begin.
+Step F must be finished before step E can begin.

2018/day8/src/main.rs

@@ -1,6 +1,5 @@
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 fn calc_metadata_sum(ints: &mut Vec<i32>) -> i32 {
     let subnode_count = ints.remove(0);
@@ -60,3 +59,22 @@ fn main() {
     let sum2 = calc_node_sum(&mut ints.clone());
     println!("part 2 sum is {}", sum2);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let mut ints: Vec<i32> = vec![2, 3, 0, 3, 10, 11, 12, 1, 1, 0, 1, 99, 2, 1, 1, 2];
+        let sum = calc_metadata_sum(&mut ints);
+        assert_eq!(sum, 138);
+    }
+
+    #[test]
+    fn test_part_two() {
+        let mut ints: Vec<i32> = vec![2, 3, 0, 3, 10, 11, 12, 1, 1, 0, 1, 99, 2, 1, 1, 2];
+        let sum = calc_node_sum(&mut ints);
+        assert_eq!(sum, 66);
+    }
+}

2018/day9/src/main.rs

@@ -4,7 +4,6 @@ use regex::Regex;
 use std::collections::VecDeque;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::iter::Iterator;
 
 fn play_game_deque(num_players: usize, max_marbles: u64) -> u64 {
     let mut game: VecDeque<u64> = VecDeque::with_capacity(max_marbles as usize);
@@ -51,3 +50,14 @@ fn main() {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_one() {
+        let score = play_game_deque(9, 25);
+        assert_eq!(score, 32);
+    }
+}