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 Go (1.6) (judge verdict: Time Limit Exceeded)

package main

import (
    "bufio"
    "os"
    "strings"
    "strconv"
    "fmt"
)

const WIDTH = 502
const HEIGHT = 502

var nrs = bufio.NewReaderSize(os.Stdin, 1000000)

func readLineToInt() []int {
    buf := make([]byte, 0, 1000000)
    for {
        l, p, e := nrs.ReadLine()
        if e != nil {
            panic(e)
        }
        buf = append(buf, l...)
        if !p {
            break
        }
    }
    line := strings.Split(string(buf), " ")
    var intLine []int
    for _, str := range line {
        n, _ := strconv.Atoi(str)
        intLine = append(intLine, n)
    }
    return intLine
}

func main() {
    nmq := readLineToInt()
    _, m, q := nmq[0], nmq[1], nmq[2]
    var mp [HEIGHT][WIDTH]int

    for i := 0; i < m; i++ {
        lr := readLineToInt()
        l, r := lr[0], lr[1]
        mp[l][r] += 1
    }

    for x := 0; x < WIDTH - 1; x++ {
        mp[0][x] += mp[0][x + 1]
    }

    for y := 1; y < HEIGHT; y++ {
        for x := 0; x < WIDTH - 1; x++ {
            mp[y][x + 1] += mp[y][x]
            mp[y][x] += mp[y - 1][x]
        }
    }

    for i := 0; i < q; i++ {
        ab := readLineToInt()
        a, b := ab[0], ab[1]
        fmt.Println(mp[b][b] - mp[b][a - 1] - mp[a - 1][b] + mp[a - 1][a - 1])
    }
}