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: Time Limit Exceeded)

    import java.io.*;
    import java.util.*;
     
    public class Main {
      public static void main (String[] args) {
        FastScanner in = new FastScanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
     
        while (in.hasNext()) {
          int N = in.nextInt();
          int M = in.nextInt();
          int Q = in.nextInt();
          int[][] table = new int[N + 1][N + 1];
     
          while (M-- > 0) {
            ++table[in.nextInt()][in.nextInt()];
          }
          
          
          
          while (Q-- > 0){
            int p = in.nextInt();
            int q = in.nextInt();
            int sum = 0;
            for (int i = p; i <= q; ++i) {
              for (int j = p; j <= q; ++j) {
                sum+=table[i][j];
              }
            }
            
            out.println(sum);
          }
        }
        
        out.close();
      }
        private static class FastScanner {
    	BufferedReader br;
    	StringTokenizer st;
     
    	public FastScanner() {
    		br = new BufferedReader(new InputStreamReader(System.in));
    	}
    	
    	public FastScanner(InputStream is) {
    		br = new BufferedReader(new InputStreamReader(is));
    	}
     
    	public FastScanner(File f) {
    		try {
    			br = new BufferedReader(new FileReader(f));
    		} catch (FileNotFoundException e) {
    			e.printStackTrace();
    		}
    	}
    	
    	// source: http://codeforces.ru/blog/entry/7805#comment-134954
    	public boolean hasNext() {
    		while (st == null || !st.hasMoreTokens()) {
    			try {
    				String line = br.readLine();
    				if (line == null) {
    					return false;
    				}
    				st = new StringTokenizer(line);
    			} catch (IOException e) {
    				throw new RuntimeException(e);
    			}
    		}	
    		return true;
    	}
     
    	public String nextLine() {
    		String ret = null;
    		try {
    			ret = br.readLine();
    		} catch (IOException e) {
    			e.printStackTrace();
    		}
     
    		return ret;
    	}
     
    	public String next() {
    		while (st == null || !st.hasMoreTokens()) {
    			try {
    				st = new StringTokenizer(br.readLine());
    			} catch (IOException e) {
    				e.printStackTrace();
    			}
    		}
    		return st.nextToken();
    	}
     
    	public int nextInt() {
    		return Integer.parseInt(next());
    	}
        }
    }