Problem:
Score: 400 points

Problem Statement

In Takahashi Kingdom, there is a east-west railroad and N cities along it, numbered 1, 2, 3, ..., N from west to east.
A company called AtCoder Express possesses M trains, and the train i runs from City L_i to City R_i (it is possible that L_i = R_i).
Takahashi the king is interested in the following Q matters:

The number of the trains that runs strictly within the section from City p_i to City q_i, that is, the number of trains j such that p_i \leq L_j and R_j \leq q_i.

Although he is genius, this is too much data to process by himself. Find the answer for each of these Q queries to help him.

Constraints

N is an integer between 1 and 500 (inclusive).

M is an integer between 1 and 200 \ 000 (inclusive).

Q is an integer between 1 and 100 \ 000 (inclusive).

1 \leq L_i \leq R_i \leq N (1 \leq i \leq M)

1 \leq p_i \leq q_i \leq N (1 \leq i \leq Q)

Input

Input is given from Standard Input in the following format:

N M Q
L_1 R_1
L_2 R_2
:
L_M R_M
p_1 q_1
p_2 q_2
:
p_Q q_Q

Output

Print Q lines. The i-th line should contain the number of the trains that runs strictly within the section from City p_i to City q_i.

Sample Input 1

2 3 1
1 1
1 2
2 2
1 2

Sample Output 1

3

As all the trains runs within the section from City 1 to City 2, the answer to the only query is 3.

Sample Input 2

10 3 2
1 5
2 8
7 10
1 7
3 10

Sample Output 2

1
1

The first query is on the section from City 1 to 7. There is only one train that runs strictly within that section: Train 1.
The second query is on the section from City 3 to 10. There is only one train that runs strictly within that section: Train 3.

Sample Input 3

10 10 10
1 6
2 9
4 5
4 7
4 7
5 8
6 6
6 7
7 9
10 10
1 8
1 9
1 10
2 8
2 9
2 10
3 8
3 9
3 10
1 10

Sample Output 3

7
9
10
6
8
9
6
7
8
10

Solution in C# (Mono 4.6.2.0) (judge verdict: Time Limit Exceeded)

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

namespace AtCoder.ABC106.D
{
    class Program
    {
        static void Main(string[] args)
        {
            // 入力値の検証は割愛
            var parameters = Console.ReadLine().Split(' ');
            var N = int.Parse(parameters[0]);
            var M = int.Parse(parameters[1]);
            var Q = int.Parse(parameters[2]);

            var trains = Enumerable.Range(1, M).Select(i =>
            {
                var tokens = Console.ReadLine().Split(' ');
                var l = int.Parse(tokens[0]);
                var r = int.Parse(tokens[1]);
                return new Train(l, r);
            }).ToList();

            var problems = Enumerable.Range(1, Q).Select(i =>
            {
                var tokens = Console.ReadLine().Split(' ');
                var p = int.Parse(tokens[0]);
                var q = int.Parse(tokens[1]);
                return new Problem(p, q);
            }).ToList();

            var takahashi = new Takahashi();

            var answers = takahashi.Answer(trains, problems);

            answers.ToList().ForEach(answer =>
            {
                Console.WriteLine(answer);
            });
        }
    }

    public class Takahashi
    {
        public IEnumerable<int> Answer(IEnumerable<Train> trains, IEnumerable<Problem> problems)
        {
            return problems.Select(problem =>
            {
                return trains.Where(train => problem.P <= train.L && train.R <= problem.Q).Count();
            });
        }
    }

    public struct Train
    {
        public Train(int l, int r)
        {
            L = l;
            R = r;
        }
        public int L { get; private set; }
        public int R { get; private set; }
    }

    public struct Problem
    {
        public Problem(int p, int q)
        {
            P = p;
            Q = q;
        }
        public int P { get; private set; }
        public int Q { get; private set; }
    }
}