From ada33c13a5ee34010583dc46ba5d606345915947 Mon Sep 17 00:00:00 2001
From: Patrick Auernig <patrick.auernig@mykolab.com>
Date: Thu, 2 Dec 2021 15:44:42 +0100
Subject: [PATCH] Add solution for 2021 day 02

---
 2021/README.md           |  2 +-
 2021/day-02/part_one.adb | 21 +++++++++++++++++++
 2021/day-02/part_two.adb | 26 ++++++++++++++++++++++++
 2021/day-02/shared.adb   | 44 ++++++++++++++++++++++++++++++++++++++++
 2021/day-02/shared.ads   | 23 +++++++++++++++++++++
 5 files changed, 115 insertions(+), 1 deletion(-)
 create mode 100644 2021/day-02/part_one.adb
 create mode 100644 2021/day-02/part_two.adb
 create mode 100644 2021/day-02/shared.adb
 create mode 100644 2021/day-02/shared.ads

diff --git a/2021/README.md b/2021/README.md
index f2bfeeb..9469830 100644
--- a/2021/README.md
+++ b/2021/README.md
@@ -3,7 +3,7 @@
 | Solved | Day | Language |
 | :----: | :-: | :------- |
 |   ✓    | 01  | Ruby     |
-|        | 02  |          |
+|   ✓    | 02  | Ada      |
 |        | 03  |          |
 |        | 04  |          |
 |        | 05  |          |
diff --git a/2021/day-02/part_one.adb b/2021/day-02/part_one.adb
new file mode 100644
index 0000000..16a39ce
--- /dev/null
+++ b/2021/day-02/part_one.adb
@@ -0,0 +1,21 @@
+with Ada.Command_Line;
+with shared;
+
+procedure part_one is
+    use Ada.Command_Line;
+    use shared;
+
+    commands : CommandVec := read_file(Argument(1));
+    depth : Integer := 0;
+    horizontal_pos : Integer := 0;
+begin
+    for cmd of commands loop
+        case cmd.direction is
+            when Forward => horizontal_pos := horizontal_pos + cmd.distance;
+            when Up => depth := depth - cmd.distance;
+            when Down => depth := depth + cmd.distance;
+        end case;
+    end loop;
+
+    put_satanized_number_line(horizontal_pos * depth);
+end part_one;
diff --git a/2021/day-02/part_two.adb b/2021/day-02/part_two.adb
new file mode 100644
index 0000000..6591858
--- /dev/null
+++ b/2021/day-02/part_two.adb
@@ -0,0 +1,26 @@
+with Ada.Command_Line;
+with shared;
+
+procedure part_two is
+    use Ada.Command_Line;
+    use shared;
+
+    commands : CommandVec := read_file(Argument(1));
+    depth : Integer := 0;
+    aim : Integer := 0;
+    horizontal_pos : Integer := 0;
+begin
+    for cmd of commands loop
+        case cmd.direction is
+            when Forward =>
+                horizontal_pos := horizontal_pos + cmd.distance;
+                depth := depth + (aim * cmd.distance);
+            when Up =>
+                aim := aim - cmd.distance;
+            when Down =>
+                aim := aim + cmd.distance;
+        end case;
+    end loop;
+
+    put_satanized_number_line(horizontal_pos * depth);
+end part_two;
diff --git a/2021/day-02/shared.adb b/2021/day-02/shared.adb
new file mode 100644
index 0000000..9a3cb71
--- /dev/null
+++ b/2021/day-02/shared.adb
@@ -0,0 +1,44 @@
+with Ada.Text_IO;
+with Ada.Strings.Unbounded;
+
+package body shared is
+    use Ada.Text_IO;
+
+    function read_file(path : String) return CommandVec is
+        use Ada.Strings.Unbounded;
+
+        commands : CommandVec;
+        infile : File_Type;
+    begin
+        open(infile, mode => in_file, name => path);
+
+        while not end_of_file(infile) loop
+            declare
+                line : Unbounded_String;
+                idx : Natural;
+                left : Unbounded_String;
+                right : Unbounded_String;
+                direction : Directions;
+                distance : Natural;
+                cmd : Command;
+            begin
+                line := To_Unbounded_String(Get_Line(infile));
+                idx := Index(line, " ", 1);
+                left := Unbounded_Slice(line, 1, idx - 1);
+                right := Unbounded_Slice(line, idx + 1, Length(line));
+                direction := Directions'Value(To_String(left));
+                distance := Natural'Value(To_String(right));
+                cmd := (direction, distance);
+                commands.append(cmd);
+            end;
+        end loop;
+
+        return commands;
+    end read_file;
+
+    procedure put_satanized_number_line(val : in Natural) is
+        img : String :=  Natural'Image(val);
+    begin
+        put_line(img(img'First + 1 .. img'Last));
+    end put_satanized_number_line;
+end shared;
diff --git a/2021/day-02/shared.ads b/2021/day-02/shared.ads
new file mode 100644
index 0000000..5adc553
--- /dev/null
+++ b/2021/day-02/shared.ads
@@ -0,0 +1,23 @@
+with Ada.Containers.Vectors;
+
+package shared is
+    use Ada.Containers;
+
+    type Directions is (Forward, Up, Down);
+
+    type Command is record
+        direction : Directions;
+        distance  : Natural;
+    end record;
+
+    package CommandVectors is new Vectors (
+        Index_Type => Natural,
+        Element_Type => Command
+    );
+
+    subtype CommandVec is CommandVectors.Vector;
+
+    function read_file(path : String) return CommandVec;
+
+    procedure put_satanized_number_line(val : in Natural);
+end shared;