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.Arrays;
import java.util.Scanner;

public class Main {

    void run() {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt(), m = sc.nextInt(), q = sc.nextInt();
        int[][] lr = new int[m][2];
        int[][] pq = new int[q][2];

        for (int i = 0; i < m; i++) {
            lr[i][0] = sc.nextInt();
            lr[i][1] = sc.nextInt();
        }
        for (int i = 0; i < q; i++) {
            pq[i][0] = sc.nextInt();
            pq[i][1] = sc.nextInt();
        }
        int[][] board = new int[n + 2][n + 2];

        for (int i = 0; i < m; i++) {
            board[lr[i][1]][lr[i][0]] += 1;
        }

        for (int y = 1; y <= n; y++) for (int x = 1; x <= n; x++) {
            board[y][x] += board[y - 1][x] + board[y][x - 1] - board[y - 1][x - 1];
        }

        for (int i = 0; i < q; i++) {
            System.out.println(query(pq[i][0], pq[i][1], board));
        }
    }

    int query(int p, int q, int[][] board) {
        return board[q][q] - board[q][p - 1] - board[p - 1][q] + board[p - 1][p - 1];
    }

    void debug(Object...os) {
        System.err.println(Arrays.deepToString(os));
    }

    public static void main(String[] args) {
        new Main().run();
    }
}