/// <summary>
/// https://adventofcode.com/2020/day/19#part2
/// </summary>
public static void Part2()
{
var groups = Input.GetGroups(19);
var ruleSet = MessageRuleSet.Parse(groups[0]);
var inputs = groups[1].Split('\n');
ruleSet[8] = MessageRule.Parse("42 | 42 8");
ruleSet[11] = MessageRule.Parse("42 31 | 42 11 31");
var count = inputs.Count(ruleSet[0].Matches);
Console.WriteLine(count);
}
public void Part2Test()
{
// Given
var groups = Input.GetGroups(19, "Part2");
var ruleSet = MessageRuleSet.Parse(groups[0]);
var inputs = groups[1].Split('\n');
// When
var oldCount = inputs.Count(ruleSet[0].Matches);
ruleSet[8] = MessageRule.Parse("42 | 42 8");
ruleSet[11] = MessageRule.Parse("42 31 | 42 11 31");
var newCount = inputs.Count(ruleSet[0].Matches);
// Then
Assert.Equal(3, oldCount);
Assert.Equal(12, newCount);
}