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 Kotlin (1.0.0) (judge verdict: Accepted)

import java.util.*
import java.io.PrintWriter



fun main(args: Array<String>){
	val cin = Scanner(System.`in`)
    val cout = PrintWriter(System.`out`)
    val n = cin.nextInt()
    val m = cin.nextInt()
    val q = cin.nextInt()

    val arr = Array<Array<Int>>(n, { Array<Int>(n, { 0 }) })
    val dp = Array<Array<Int>>(n, { Array<Int>(n, { 0 }) })

    for (i in 0..m-1) {
        arr[cin.nextInt() - 1][cin.nextInt() - 1] += 1
    }

    for (d in 0..n-1) {
        for (i in 0..n-1) {
            if (i + d >= n) {
                break
            }
            if (d > 1) {
                dp[i][i + d] = arr[i][i + d] + dp[i][i + d - 1] + dp[i + 1][i + d] - dp[i + 1][i + d - 1]
            } else if (d > 0) {
                dp[i][i + d] = arr[i][i + d] + dp[i][i + d - 1] + dp[i + 1][i + d]
            } else {
                dp[i][i + d] = arr[i][i + d]
            }
        }
    }
    for (i in 0..q-1) {
        cout.println(dp[cin.nextInt() - 1][cin.nextInt() - 1])
    }
    
    cout.flush()
}















class Point(x: Int, y: Int) : Comparable<Point> {
    val x = x
    val y = y
    
    override operator fun compareTo(other : Point) : Int {
        if (x > other.x) {
            return 1
        } else if (x < other.x) {
            return -1
        } else {
            if (y > other.y) {
                return 1
            } else if (y < other.y) {
                return -1
            } else {
                return 0
            }
        }
    }


    override fun equals(other : Any?) : Boolean {
        if (this == other) {
            return true
        }
        if (javaClass != other?.javaClass) {
            return false
        }
        other as Point
        if (x == other.x && y == other.y) {
            return true
        }
        return false
    }
}





inline fun <reified T, reified E> segTree(m: Int, noinline f: (T, T)->T, noinline g: (T, E)->T, noinline h:(E, E)->E, ti: T, ei: E, ini: Array<T>): SegTree<T, E> {
    val n = cover(m)
    val ini_tree = Array<T>(2*n - 1, { i ->
        if (i < m) {
            ini[i]
        } else {
            ti
        }
    })
    val lazy = Array<E>(2*n - 1, { ei })
    return SegTree(n, f, g, h, ti, ei, ini_tree, lazy)
}

fun cover(m: Int): Int {
    var n = 1
    while (n < m) {
        n *= 2
    }
    return n
}

fun cover_d(m: Int): Int {
    var d = 0
    var n = 1
    while (n < m) {
        n *= 2
        d += 1
    }
    return d
}

class SegTree<T, E> (n: Int, f: (T, T)->T, g: (T, E)->T, h: (E, E)->E, ti: T, ei: E, node: Array<T>, lazy: Array<E>) {
    val n = n
    val f = f
    val g = g
    val h = h
    val ti = ti
    val ei = ei
    val node = node
    val lazy = lazy
    val size = node.size
    val height = cover_d(n)

    inline fun trans(i: Int): Int {
        return i + n - 1
    }

    inline fun left(i: Int): Int {
        return 2*i + 1
    }

    inline fun right(i: Int): Int {
        return 2*i + 2
    }

    inline fun parent(i: Int): Int {
        if (i == 0) {
            return -1
        }
        return (i - 1)/2
    }

    inline fun ancestor(i: Int, d: Int): Int {
        return ((i + 1) shr d) - 1
    }

    inline fun isRight(i: Int): Boolean {
        return ((i and 1) == 0)
    }

    inline fun isLeaf(i: Int): Boolean {
        return (left(i) > size)
    }

    inline fun reflect(k: Int): T {
        if (k >= size) {
            return ti
        }
        if (lazy[k] == ei) {
            return node[k]
        }
        return g(node[k], lazy[k])
    }

    inline fun eval(k: Int) {
        if (lazy[k] == ei) {
            return
        }
        if (left(k) < size) {
            lazy[left(k)] = h(lazy[left(k)], lazy[k])
            lazy[right(k)] = h(lazy[right(k)], lazy[k])
        }
        node[k] = reflect(k)
        lazy[k] = ei
    }

    inline fun thrust(k: Int) {
        // if (k > 0) {
        //     thrust(parent(k))
        // }
        for (i in 0..height) {
            eval(ancestor(k, height - i))
        }
        // eval(k)
    }

    inline fun recalc(k: Int) {
        var i = parent(k)
        while (i >= 0) {
            node[i] = f(reflect(left(i)), reflect(right(i)))
            i = parent(i)
        }
    }

    fun update(a: Int, b: Int, x: E) {
        val l0 = trans(a)
        val r0 = trans(b)
        thrust(l0)
        thrust(r0 - 1)

        var l = l0
        var r = r0
        while (l < r) {
            if (isRight(l)) {
                lazy[l] = h(lazy[l], x)
                l += 1
            }
            if (isRight(r)) {
                r -= 1
                lazy[r] = h(lazy[r], x)
            }
            l = l shr 1
            r = r shr 1
        }
        recalc(l0)
        recalc(r0 - 1)
    }

    fun set_val(a: Int, x: T) {
        val ta = trans(a)
        thrust(ta)
        node[ta] = x
        lazy[ta] = ei
        recalc(ta)
    }

    fun query(a: Int, b: Int): T {
        var l = trans(a)
        var r = trans(b)
        thrust(l)
        thrust(r - 1)

        var vl = ti
        var vr = ti

        while (l < r) {
            if (isRight(l)) {
                vl = f(vl, reflect(l))
                l += 1
            }
            if (isRight(r)) {
                r -= 1
                vr = f(reflect(r), vr)
            }
        }
        
        return f(vl, vr)
    }
}