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using System;
using System.IO;
using System.Linq;
namespace AOC
{
internal class Run
{
private static int[] Double(int[] arr, int low, int result)
{
int high = arr.Length - 1;
int sum = arr[low] + arr[high];
while (low < high && sum != result)
{
if (sum < result)
low++;
else
high--;
sum = arr[low] + arr[high];
}
if (low == high)
{
return new[] {0, 0};
}
return new[] {arr[low], arr[high]};
}
private static int[] Triple(int[] arr, int result)
{
for (int i = 0; i < arr.Length; i++)
{
int remainder = result - arr[i];
int[] d = Double(arr, i, remainder);
if (d.Sum() != 0)
{
return new[] {arr[i], d[0], d[1]};
}
}
return new[] {0, 0};
}
public static void Main(string[] args)
{
string text = File.ReadAllText("input");
string[] numsStr = text.Split('\n');
numsStr[numsStr.Length - 1] = "2020"; // Some weird newline character ig
var clock = System.Diagnostics.Stopwatch.StartNew();
int[] nums = Array.ConvertAll(numsStr, int.Parse).OrderBy(i => i).ToArray();
int[] d = Double(nums, 0, 2020);
int[] t = Triple(nums, 2020);
Console.WriteLine(d[0] * d[1]);
Console.WriteLine(t[0] * t[1] * t[2]);
clock.Stop();
Console.WriteLine("TIME: " + ((float)clock.ElapsedMilliseconds / 1000.0).ToString("n6") + " seconds");
}
}
}
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