Problem:
Sale Result

There is data on sales of your company. Your task is to write a program which identifies good workers.

The program should read a list of data where each item includes the employee ID i, the amount of sales q and the corresponding unit price p. Then, the program should print IDs of employees whose total sales proceeds (i.e. sum of p × q) is greater than or equal to 1,000,000 in the order of inputting. If there is no such employees, the program should print "NA". You can suppose that n < 4000, and each employee has an unique ID. The unit price p is less than or equal to 1,000,000 and the amount of sales q is less than or equal to 100,000.

Input

The input consists of several datasets. The input ends with a line including a single 0. Each dataset consists of:

n (the number of data in the list)
i p q
i p q
:
:
i p q

Output

For each dataset, print a list of employee IDs or a text "NA"

Sample Input

4
1001 2000 520
1002 1800 450
1003 1600 625
1001 200 1220
2
1001 100 3
1005 1000 100
2
2013 5000 100
2013 5000 100
0

Output for the Sample Input

1001
1003
NA
2013

Solution in C# (judge verdict: Accepted)

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

namespace AOJ0100
{
    class Program
    {
        static void Main()
        {
            ReadInputs()
                .Select(
                    s =>
                        s.GroupBy(r => r.Id,
                            (id, records) => new {Id = id, Sales = records.Sum(r => r.UnitPrice*r.Quantity)})
                            .Where(t => t.Sales >= 1000000)
                            .Select(t => t.Id.ToString())
                            .DefaultIfEmpty("NA"))
                .ForEach(results => results.ForEach(Console.WriteLine));

        }

        private static IEnumerable<IEnumerable<Record>> ReadInputs()
        {
            
            IEnumerable<Record> dataSet;
            while ((dataSet = ReadDataSet()) != null)
            {
                yield return dataSet;
            }

        }

        private static IEnumerable<Record> ReadDataSet()
        {
            var count = int.Parse(Console.ReadLine() ?? "0");
            return count == 0 ? null : ReadDataSetImpl(count);
        }

        private static IEnumerable<Record> ReadDataSetImpl(int count)
        {
            while (count-- > 0)
            {
                // ReSharper disable once PossibleNullReferenceException
                var data = Console.ReadLine().Split(' ').Select(long.Parse).ToArray();
                yield return new Record {Id = data[0], UnitPrice = data[1], Quantity = data[2]};
            }
        }
    }

    class Record
    {
        public long Id { get; set; }
        public long UnitPrice { get; set; }
        public long Quantity { get; set; }
    }

    static class EnumerableExtensions
    {
        public static void ForEach<T>(this IEnumerable<T> source, Action<T> action)
        {
            foreach (var item in source)
            {
                action(item);
            }
        }
    }
}