# Day 06
## Common
<!-- livebook:{"reevaluate_automatically":true} -->
```elixir
# Time: 7 15 30
# Distance: 9 40 200
example_input = [{7, 9}, {15, 40}, {30, 200}]
# Time: 41 66 72 66
# Distance: 244 1047 1228 1040
real_input = [{41, 244}, {66, 1047}, {72, 1228}, {66, 1040}]
defmodule Race do
def count_possibilities({time, distance}) do
0..time
|> Stream.map(&((time - &1) * &1))
|> Stream.drop_while(&(&1 <= distance))
|> Stream.take_while(&(&1 > distance))
|> Enum.count()
end
end
ExUnit.start(autorun: false)
defmodule RaceTest do
use ExUnit.Case, async: true
describe "count_possibilities/1" do
test "returns correct count for {7, 9}" do
assert 4 = Race.count_possibilities({7, 9})
end
test "returns correct count for {30, 200}" do
assert 9 = Race.count_possibilities({30, 200})
end
end
end
ExUnit.run()
```
## Part 1
<!-- livebook:{"reevaluate_automatically":true} -->
```elixir
# Time: 7 15 30
# Distance: 9 40 200
example_input = [{7, 9}, {15, 40}, {30, 200}]
# Time: 41 66 72 66
# Distance: 244 1047 1228 1040
real_input = [{41, 244}, {66, 1047}, {72, 1228}, {66, 1040}]
real_input
|> Enum.map(&Race.count_possibilities/1)
|> Enum.product()
```
## Part 2
<!-- livebook:{"reevaluate_automatically":true} -->
```elixir
# Time: 7 15 30
# Distance: 9 40 200
example_input = {71530, 940_200}
# Time: 41 66 72 66
# Distance: 244 1047 1228 1040
real_input = {41_667_266, 244_104_712_281_040}
Race.count_possibilities(real_input)
```
