···

       
37
       
 
       
  moves

     

       
38
       
 
       
  |> String.split("\n", trim: true)

     

       
39
       
 
       
  |> Enum.map(fn move ->

     

       
40
       
-
       
    result = Regex.named_captures(~r/move (?<count>\d+) from (?<from>\d) to (?<to>\d)/, move)

     

       
41
       
-
       


     

       
42
       
-
       
    %{

     

       
43
       
-
       
      count: String.to_integer(result["count"]),

     

       
44
       
-
       
      from: String.to_integer(result["from"]),

     

       
45
       
-
       
      to: String.to_integer(result["to"])

     

       
46
       
-
       
    }

     

       
47
       
 
       
  end)

     

       
48
       
 
       


     

       
49
       
 
       
crates =

     
···

       
60
       
 
       
    end)

     

       
61
       
 
       
  end)

     

       
62
       
 
       
  |> Enum.zip()

     

       
63
       
-
       
  |> Enum.map(&Tuple.to_list/1)

     

       
64
       
-
       
  |> Enum.map(fn column -> Enum.drop_while(column, &is_nil/1) end)

     

       
65
       
 
       
  |> Enum.with_index(1)

     

       
66
       
 
       
  |> Map.new(fn {v, k} -> {k, v} end)

     

       
67
       
 
       
```

     
···

       
91
       
 
       


     

       
92
       
 
       
    Map.update!(columns, to, &(moved ++ &1))

     

       
93
       
 
       
  end

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
94
       
 
       
end

     

       
95
       
 
       
```

     

       
96
       
 
       


     

       
97
       
 
       
<!-- livebook:{"output":true} -->

     

       
98
       
 
       


     

       
99
       
 
       
```

     

       
100
       
-
       
{:module, Day05, <<70, 79, 82, 49, 0, 0, 10, ...>>, {:move, 3}}

     

       
101
       
 
       
```

     

       
102
       
 
       


     

       
103
       
 
       
## Task 1

     

       
104
       
 
       


     

       
105
       
 
       
```elixir

     

       
106
       
-
       
moves

     

       
107
       
-
       
|> Enum.reduce(crates, &Day05.move/2)

     

       
108
       
-
       
|> Enum.sort()

     

       
109
       
-
       
|> Enum.map(fn {_, v} -> hd(v) end)

     

       
110
       
 
       
```

     

       
111
       
 
       


     

       
112
       
 
       
<!-- livebook:{"output":true} -->

     
···

       
118
       
 
       
## Task 2

     

       
119
       
 
       


     

       
120
       
 
       
```elixir

     

       
121
       
-
       
moves

     

       
122
       
-
       
|> Enum.reduce(crates, &Day05.move(&1, &2, false))

     

       
123
       
-
       
|> Enum.sort()

     

       
124
       
-
       
|> Enum.map(fn {_, v} -> hd(v) end)

     

       
125
       
 
       
```

     

       
126
       
 
       


     

       
127
       
 
       
<!-- livebook:{"output":true} -->

     

···

       
37
       
 
       
  moves

     

       
38
       
 
       
  |> String.split("\n", trim: true)

     

       
39
       
 
       
  |> Enum.map(fn move ->

     

       
40
       
+
       
    Regex.named_captures(~r/move (?<count>\d+) from (?<from>\d) to (?<to>\d)/, move)

     

       
41
       
+
       
    |> Map.new(fn {k, v} -> {String.to_atom(k), String.to_integer(v)} end)

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
42
       
 
       
  end)

     

       
43
       
 
       


     

       
44
       
 
       
crates =

     
···

       
55
       
 
       
    end)

     

       
56
       
 
       
  end)

     

       
57
       
 
       
  |> Enum.zip()

     

       
58
       
+
       
  |> Enum.map(fn column -> column |> Tuple.to_list() |> Enum.drop_while(&is_nil/1) end)

     

       
0
       
 
       

     

       
59
       
 
       
  |> Enum.with_index(1)

     

       
60
       
 
       
  |> Map.new(fn {v, k} -> {k, v} end)

     

       
61
       
 
       
```

     
···

       
85
       
 
       


     

       
86
       
 
       
    Map.update!(columns, to, &(moved ++ &1))

     

       
87
       
 
       
  end

     

       
88
       
+
       


     

       
89
       
+
       
  def eval(crates, moves, reverse? \\ true) do

     

       
90
       
+
       
    moves

     

       
91
       
+
       
    |> Enum.reduce(crates, &Day05.move(&1, &2, reverse?))

     

       
92
       
+
       
    |> Enum.sort()

     

       
93
       
+
       
    |> Enum.map(fn {_, v} -> hd(v) end)

     

       
94
       
+
       
  end

     

       
95
       
 
       
end

     

       
96
       
 
       
```

     

       
97
       
 
       


     

       
98
       
 
       
<!-- livebook:{"output":true} -->

     

       
99
       
 
       


     

       
100
       
 
       
```

     

       
101
       
+
       
{:module, Day05, <<70, 79, 82, 49, 0, 0, 13, ...>>, {:eval, 3}}

     

       
102
       
 
       
```

     

       
103
       
 
       


     

       
104
       
 
       
## Task 1

     

       
105
       
 
       


     

       
106
       
 
       
```elixir

     

       
107
       
+
       
Day05.eval(crates, moves)

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
108
       
 
       
```

     

       
109
       
 
       


     

       
110
       
 
       
<!-- livebook:{"output":true} -->

     
···

       
116
       
 
       
## Task 2

     

       
117
       
 
       


     

       
118
       
 
       
```elixir

     

       
119
       
+
       
Day05.eval(crates, moves, false)

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
120
       
 
       
```

     

       
121
       
 
       


     

       
122
       
 
       
<!-- livebook:{"output":true} -->