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 Rust (1.15.1) (judge verdict: Accepted)

use std::io;
use std::str::FromStr;

fn main() {
    let nmq: Vec<i32> = reads();
    let (n,m,q) = (nmq[0], nmq[1], nmq[2]);
    let mut acc : Vec<Vec<i32>> = vec![vec![0; (nmq[0]+10) as usize]; (nmq[0]+10) as usize];
    for _ in 0..m {
        let xs : Vec<usize> = reads();
        acc[xs[0]-1][xs[1]] += 1;
    }

    for b in 0..n {
        for e in b+1..n+1 {
            acc[b as usize][e as usize] += acc[b as usize][(e-1) as usize];
        }
    }

    for e in 1..n+1 {
        for ib in 0..e {
            acc[(e-ib-1) as usize][e as usize] += acc[(e-ib) as usize][e as usize];
        }
    }

    for _ in 0..q {
        let xs : Vec<usize> = reads();
        println!("{}", acc[xs[0]-1][xs[1]]);
    }
}



#[allow(dead_code)]
fn getline() -> String {
    let mut ln = String::new();
    io::stdin().read_line(&mut ln).ok();
    ln.trim().to_string()
}

#[allow(dead_code)]
fn read<T>() -> T where T : FromStr {
    let mut ln = String::new();
    io::stdin().read_line(&mut ln).ok();
    ln.trim().parse().ok().unwrap()
}

#[allow(dead_code)]
fn reads<T>() -> Vec<T> where T : FromStr {
    let mut ln = String::new();
    io::stdin().read_line(&mut ln).ok();
    ln.trim().split_whitespace().map(|x| x.parse().ok().unwrap()).collect()
}