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: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;

namespace AtCoder
{
    class Program
    {
        private static string Read() { return Console.ReadLine(); }
        private static int ReadInt() { return int.Parse(Read()); }
        private static long ReadLong() { return long.Parse(Read()); }
        private static double ReadDouble() { return double.Parse(Read()); }
        private static int[] ReadInts() { return Array.ConvertAll(Read().Split(), int.Parse); }
        private static long[] ReadLongs() { return Array.ConvertAll(Read().Split(), long.Parse); }
        private static double[] ReadDoubles() { return Array.ConvertAll(Read().Split(), double.Parse); }

        class Rail
        {
            public readonly int L;
            public readonly int R;
            public Rail(int[] args)
            {
                L = args[0];
                R = args[1];
            }
        }
        class Solver
        {
            private int[][] count = new int[501][];
            public Solver(Rail[] rails)
            {
                for (int i = 1; i <= 500; ++i) { count[i] = new int[501]; }
                foreach (var rail in rails)
                {
                    for (int i = 1; i <= rail.L; ++i) { ++count[i][rail.R]; }
                }
            }
            public int Solve(Rail query)
            {
                int sum = 0;
                for (int i = 1; i <= query.R; ++i) { sum += count[query.L][i]; }
                return sum;
            }
        }
        static void Main(string[] args)
        {
            int[] V1 = ReadInts();
            int N = V1[0];
            int M = V1[1];
            int Q = V1[2];
            var rails = new Rail[M];
            for (int i = 0; i < M; ++i) { rails[i] = new Rail(ReadInts()); }
            var solver = new Solver(rails);
            var queries = new Rail[Q];
            for (int i = 0; i < Q; ++i) { queries[i] = new Rail(ReadInts()); }
            foreach (var query in queries)
            {
                Console.WriteLine(solver.Solve(query));
            }
        }
    }
}