AdventOfCode2021/AdventOfCode/2021/Day1.cs

namespace AdventOfCode._2021;
using System.Collections;

public class Day1
{
    public void Part1()
    {
        var input = File.ReadAllLines("2021/input/day1.txt").AsInt();
        int previous = input.First();
        int count = 0;
        foreach (var i in input)
        {
            if (i > previous)
            {
                count += 1;
            }

            previous = i;
        }

        Console.WriteLine(count);
    }

    public void Part2()
    {
        var input = File.ReadAllLines("2021/input/day1.txt").AsInt().ToList();

        int previous = input[0] + input[1] + input[2];
        int count = 0;
        for (int i = 1; i < input.Count; i++)
        {
            if (i + 2 > input.Count - 1)
            {
                break;
            }

            int sum = input[i] + input[i + 1] + input[i + 2];

            if (sum > previous)
            {
                count += 1;
            }

            previous = sum;
        }

        Console.WriteLine(count); // first input isn't counted.
    }
}