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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {
    public static void main(String args[]) {
        try (Scanner in = new Scanner(System.in)) {
            int N = in.nextInt();
            int M = in.nextInt();
            int Q = in.nextInt();

            int[] L = new int[M];
            int[] R = new int[M];
            int[][] count = new int[N][N];
            for (int i = 0; i < M; i++) {
                L[i] = in.nextInt() - 1;
                R[i] = in.nextInt() - 1;
                count[L[i]][R[i]]++;
            }

            TwoDimensionalCumulativeSum cumsum = new TwoDimensionalCumulativeSum(count);

            int[] p = new int[Q];
            int[] q = new int[Q];
            for (int i = 0; i < Q; i++) {
                p[i] = in.nextInt() - 1;
                q[i] = in.nextInt() - 1;
                System.out.println(cumsum.cumulativeSum(p[i], p[i], q[i] + 1, q[i] + 1));
            }

        }
    }

}

class TwoDimensionalCumulativeSum {
    private int[][] sum;

    public TwoDimensionalCumulativeSum(int[][] values) {
        int R = values.length;
        int C = values[0].length;
        sum = new int[R + 1][C + 1];
        for (int r = 0; r < R; r++) {
            for (int c = 0; c < C; c++) {
                sum[r + 1][c + 1] = sum[r + 1][c] + sum[r][c + 1] - sum[r][c] + values[r][c];
            }
        }
    }

    public int cumulativeSum(int startRInclusive, int startCInclusive, int endRExclusive, int endCExclusive) {
        return sum[startRInclusive][startCInclusive] - sum[endRExclusive][startCInclusive] - sum[startRInclusive][endCExclusive] + sum[endRExclusive][endCExclusive];
    }
}