ARC045のB問題(未完成)です。 / C#

arc045_B_unfinished.cs

using System;
using System.Collections.Generic;

class Program
{
    static void Main(string[] args)
    {
        var l = ReadInt();
        var N = l[0];
        var M = l[1];
        var s = new List<int>();
        var t = new List<int>();
        var imos = new int[N + 2];
        var x = new List<int>();

        for (var i = 0; i < M; ++i )
        {
            var l2 = ReadInt();
            s.Add(l2[0]);
            t.Add(l2[1]);
            imos[l2[0]]++;
            imos[l2[1] + 1]--;
        }
        for(var i = 1; i < N + 2; i++ )
        {
            imos[i] += imos[i - 1];
        }
        for (var i = 0; i < M; ++i )
        {
            x.Add(i);
            for (var j = s[i]; j <= t[i]; j++ )
            {
                if (imos[j] - 1 < 1 )
                {
                    x.Remove(i);
                    break;
                }
            }
        }

        Console.WriteLine(x.Count);
        foreach(var i in x )
        {
            Console.WriteLine(i + 1);
        }


    }

    static List<int> ReadInt ()
    {
        var input = Console.ReadLine();
        var ret = new List<int>();

        foreach (var numstr in input.Split() )
        {
            ret.Add(int.Parse(numstr));
        }
        return ret;
    }
}