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;
using System.Numerics;

namespace AtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            //[summary]D - AtCoder Express 2
            var line = ReadLine();
            int n = line[0];
            int m = line[1];
            int q = line[2];

            //すべての列車の本数を取得
            var trains = ReadLines(m).ToList();
            
            for(int i = 0; i < q; i++)
            {
                line = ReadLine();
                int start = line[0];
                int end = line[1];

                var count = CountTrains(trains, start, end);
                Console.WriteLine(count);
            }
        }

        static int CountTrains(List<List<int>> trains,int start, int end)
        {
            int count = 0;

            foreach(var train in trains)
            {
                if (train[0] >= start && train[1] <= end)
                {
                    count++;
                }
            }

            return count;
        }

        static List<int> ReadLine()
        {
            var line = Console.ReadLine().TrimEnd();
            var array = line.Split(' ');
            var numbers = new List<int>();

            foreach (var s in array)
            {
                int num = int.Parse(s);
                numbers.Add(num);
            }

            return numbers;
        }

        static IEnumerable<List<int>> ReadLines(int count)
        {
            //[summary]コンソールの値を読み込む

            for (int i = 0; i < count; i++)
            {
                string line = Console.ReadLine().TrimEnd();
                var array = line.Split(' ');

                var numbers = new List<int>();

                foreach (var s in array)
                {
                    int num = int.Parse(s);
                    numbers.Add(num);
                }

                yield return numbers;
            }
        }
    }
}