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 C++14 (GCC 5.4.1) (judge verdict: Accepted)


#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <map>
#include <set>

#ifndef U_L_LONG
typedef unsigned long long ULLONG;
#endif
#ifndef L_LONG
typedef long long LLONG;
#endif
template <class _T> static _T tp_abs(const _T& a) {
	//	usage:  tp_abs<type name>(a);
	return ((a < 0) ? (a * -1) : a);
}
template <class _T> static _T tp_min(_T a, _T b) {
	return a < b ? a : b;
}
template <class _T> static _T tp_max(_T a, _T b) {
	return a > b ? a : b;
}
template<class _T> static void get1int(_T& a) {
	const char* fmt = " %d";
	if (sizeof(_T) == sizeof(long long)) {
		fmt = " %lld";
	}

	if (scanf(fmt, &a) < 0) {
		printf("g1int Error\n");
	}
}
template<class _T> static void get2int(_T& a, _T& b) {
	const char* fmt = " %d %d";
	if (sizeof(_T) == sizeof(long long)) {
		fmt = " %lld %lld";
	}

	if (scanf(fmt, &a, &b) < 0) {
		printf("g2int Error\n");
	}
}
template<class _T> static void get3int(_T& a, _T& b, _T& c) {
	const char* fmt = " %d %d %d";
	if (sizeof(_T) == sizeof(long long)) {
		fmt = " %lld %lld %lld";
	}

	if (scanf(fmt, &a, &b, &c) < 0) {
		printf("g3int Error\n");
	}
}
template <class _T> static void tp_swap(_T& right, _T& left) {
	//	usage:  tp_swap<type name>(a, b);
	_T tmp = right;
	right = left;
	left = tmp;
}
static void getstring(char* buff) {
	if (scanf(" %s", buff) < 0) {
		printf("getstr error!\n");
	}
}


static void ABC106D_AtCoderExpress2();

#if 1
int main()
{
	ABC106D_AtCoderExpress2();
	fflush(stdout);
	return 0;
}
#endif

static void ABC106D_AtCoderExpress2()
{
	int N, M, Q;
	get3int(N, M, Q);

	auto pqStat = new int[N][501];
	memset(pqStat, 0, sizeof(int) * N * 501);
	for (int i = 0; i < M; i++) {
		int l, r;
		get2int(l, r); l--; r--;
		pqStat[l][r]++;
	}

	auto pqSum = new int[N][501];
	memset(pqSum, 0, sizeof(int) * N * 501);
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) {
			for (int l = i; l <= j; l++) {
				for (int r = l; r <= j; r++) {
					pqSum[i][j] += pqStat[l][r];
				}
			}
		}
	}

	auto ans = new int[Q];
	for (int i = 0; i < Q; i++) {
		int p, q;
		get2int(p, q); p--; q--;
		ans[i] = pqSum[p][q];
	}

	for (int i = 0; i < Q; i++) {
		printf("%d\n", ans[i]);
	}

	delete[] ans;
	delete[] pqStat;
	delete[] pqSum;
}