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)

pub mod io {
    use std;
    use std::str::FromStr;

    pub struct Scanner<'a> {
        iter: std::str::SplitWhitespace<'a>,
    }

    impl<'a> Scanner<'a> {
        pub fn new(s: &'a str) -> Scanner<'a> {
            Scanner {
                iter: s.split_whitespace(),
            }
        }

        pub fn next<T: FromStr>(&mut self) -> T {
            let s = self.iter.next().unwrap();
            if let Ok(v) = s.parse::<T>() {
                v
            } else {
                panic!("Parse error")
            }
        }

        pub fn next_vec_len<T: FromStr>(&mut self) -> Vec<T> {
            let n: usize = self.next();
            self.next_vec(n)
        }

        pub fn next_vec<T: FromStr>(&mut self, n: usize) -> Vec<T> {
            (0..n).map(|_| self.next()).collect()
        }
    }

    pub fn read_string() -> String {
        use std::io::Read;

        let mut s = String::new();
        std::io::stdin().read_to_string(&mut s).unwrap();
        s
    }

    pub fn read_line() -> String {
        let mut s = String::new();
        std::io::stdin().read_line(&mut s).unwrap();
        s.trim_right().to_owned()
    }
}

macro_rules! input {
    ($($r:tt)*) => {
        let con = io::read_string();
        let mut sc = io::Scanner::new(&con);
        input_inner!{sc, $($r)*}
    };
}

macro_rules! input_inner {
    ($sc:expr) => {};
    ($sc:expr, ) => {};

    ($sc:expr, $var:ident : [ $t:tt ; $len:expr ], $($r:tt)*) => {
        let $var: Vec<_> = (0..$len).map(|_| read_value!($sc, $t)).collect();
        input_inner!{$sc, $($r)*}
    };

    ($sc:expr, $var:ident : $t:ty, $($r:tt)*) => {
        let $var: $t = read_value!($sc, $t);
        input_inner!{$sc, $($r)*}
    };
}

macro_rules! read_value {
    ($sc:expr, ( $($t:tt),* )) => {
        ( $(read_value!($sc, $t)),* )
    };

    ($sc:expr, u1) => {
        read_value!($sc, usize) - 1
    };

    ($sc:expr, $t:ty) => {
        $sc.next::<$t>()
    };
}

//-----

fn main() {
    input!{
        n: usize,
        m: usize,
        q: usize,
        ts: [(u1, u1); m],
        qs: [(u1, u1); q],
    }

    let mut tbl = vec![vec![0; n]; n];
    for (l, r) in ts {
        for r in tbl[l][r..n].iter_mut() {
            *r += 1;
        }
    }

    for (p, q) in qs {
        let ans: usize = tbl[p..n].iter().map(|r| r[q]).sum();
        println!("{}", ans);
    }
}