H. Гонка со временем

// Sad story about Ruby, Python and (N == 10**5) problems... =/

using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;

namespace scripts_are_not_good_enof
{
    class JobDoneException: Exception {  }

    class Pupil: IComparable {
        private static int encounter = 0;
        public int house, speed, id;
        public double reach_time;
        public bool lifted;

        public Pupil(int house, int speed){
            Pupil.encounter += 1;
            this.id += encounter;

            this.house = house;
            this.speed = speed;
            this.reach_time = (double)house/speed;
            this.lifted = false;
        }

        public double cur_pos(double time){
            return Math.Max(0, this.house - this.speed*time);
        }

        public int CompareTo(Object other){
            return (Math.Abs(this.reach_time - (other as Pupil).reach_time) < double.Epsilon) ? 0 :
                   (this.reach_time > (other as Pupil).reach_time) ? -1 : 1;
        }
    }

    class Program
    {
        public static double time = 0;
        public static int our_speed;
        public static List<String> ans;
        public static List<Pupil> pupils;

        static String format_double(double n){
            var res = n.ToString().Replace(',', '.');
            if (res.IndexOf('.') == -1) res += ".0";
            return res;
        }

        static void DriveBy(Pupil pupil){
            // route to meet given pupil and lift him to the school
            double cur_pos = pupil.cur_pos(time);

            if (cur_pos < double.Epsilon || our_speed < pupil.speed)
                throw new JobDoneException();
            var closing_speed = our_speed + pupil.speed;
            ans.Add(String.Format("{0} {1}",
                                  pupil.id,
                                  format_double(cur_pos*our_speed/closing_speed)
                                 ));
            time += 2*cur_pos/closing_speed;
            pupil.lifted = true;
        }

        public static List<int> parse_int(String s){
            return s.Split().Select(x => int.Parse(x)).ToList();
        }

        public static void Main(string[] args)
        {
            /*
            var input = new StreamReader("in.txt");
            var output = new StreamWriter("out.txt");
            /*/
            var input = new StreamReader("race.in");
            var output = new StreamWriter("race.out");
            //*/

            ans = new List<String>();
            pupils = new List<Pupil>();

            var inp = parse_int(input.ReadLine());
            int n = inp[0]; our_speed = inp[1];
            for (int i = 0; i < n; i++){
                inp = parse_int(input.ReadLine());
                pupils.Add(new Pupil(inp[0], inp[1]));
            }
            pupils.Sort();

            try {
                for (int i = 0; i < pupils.Count(); i++) DriveBy(pupils[i]);
            } catch (JobDoneException) { }

            output.WriteLine(format_double(
                Math.Max(time,
                (pupils.Select(ppl => ppl.lifted ? 0 : ppl.reach_time).ToList().Max() ))
            ));
            output.WriteLine( ans.Count() );
            foreach (String line in ans) { output.WriteLine(line); }

            output.Close();
        }

    }
}