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continuous-integration/drone/push Build is passing Details

This commit is contained in:
Ben Harris 2021-12-17 17:00:31 -05:00
parent 1938202174
commit 8459671c89
2 changed files with 29 additions and 4 deletions
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2
aoc2021.test/DayTests.cs
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@ -37,7 +37,7 @@ public class DayTests
[DataRow(typeof(Day14), "5656", "12271437788530")]
[DataRow(typeof(Day15), "702", "2955")]
[DataRow(typeof(Day16), "852", "19348959966392")]
[DataRow(typeof(Day17), "12090", "")]
[DataRow(typeof(Day17), "12090", "5059")]
public void CheckAllDays(Type dayType, string part1, string part2)
{
var s = Stopwatch.StartNew();

31
aoc2021/Day17.cs
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@ -6,7 +6,7 @@
public sealed class Day17 : Day
{
private readonly List<int> _target;
public Day17() : base(17, "Trick Shot")
{
_target = Input.First()
@ -24,5 +24,30 @@ public sealed class Day17 : Day
return (initialYVelocity + 1) * initialYVelocity / 2;
}
public override object Part2() => "";
}
public override object Part2()
{
var successfulVelocities = new HashSet<(int x, int y)>();
var xMin = 1;
while (xMin * (xMin + 1) / 2 < _target[0]) xMin++;
for (var x = xMin; x <= _target[1]; x++)
for (var y = _target[2]; y < Math.Abs(_target[2]); y++)
{
int xVelocity = x, yVelocity = y, xPos = 0, yPos = 0;
while (xPos <= _target[1] && yPos >= _target[2])
{
xPos += xVelocity;
yPos += yVelocity;
if (xPos >= _target[0] && xPos <= _target[1] && yPos >= _target[2] && yPos <= _target[3])
successfulVelocities.Add((x, y));
xVelocity = xVelocity == 0 ? 0 : xVelocity - 1;
yVelocity--;
}
}
return successfulVelocities.Count;
}
}