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 <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
#include <functional>

using namespace std;

template <class It> string join(It i1, It i2)
{
    ostringstream ss;
    for (auto it = i1; it != i2; ++it)
        ss << ((it == i1) ? "" : ", ") << (*it);
    return ss.str();
}

void Print() { cout << endl; }
template <class Head, class... Args> void Print(Head &&head, Args&&... args)
{
    cout << head;
    Print(args...);
}

#ifdef DEBUG
#define Dump(x) cerr << #x << " = " << x << endl;
#define Dumps(x) cerr << #x << " : { " << join(x.begin(), x.end()) << " }" << endl;
#else
#define Dump(x)
#define Dumps(x)
#endif


using city_t = int;
using train_t = int;


int main()
{
    city_t N;
    train_t M;
    int Q;
    cin >> N >> M >> Q;

    vector<vector<size_t>> T(N, vector<size_t>(N, 0));
    for (train_t i = 0; i < M; ++i)
    {
        city_t l, r;
        cin >> l >> r;
        ++T[l - 1][r - 1];
    }

    vector<vector<size_t>> S(N, vector<size_t>(N, 0));
    S[0][0] = T[0][0];
    for (city_t i = 1; i < N; ++i)
    {
        S[i][0] = S[i - 1][0] + T[i][0];
        S[0][i] = S[0][i - 1] + T[0][i];
    }
    for (city_t i = 1; i < N; ++i)
        for (city_t j = 1; j < N; ++j)
            S[i][j] = (S[i - 1][j] + S[i][j - 1] - S[i - 1][j - 1]) + T[i][j];

    // S[i][j]: T[0~i][0~j]
    
    for (int i = 0; i < Q; ++i)
    {
        int p, q;
        cin >> p >> q;
        --p, --q;

        int n = S[q][q];
        if (p > 0)
            n -= (S[p - 1][q] + S[q][p - 1] - S[p - 1][p - 1]);
        
        cout << n << endl;
    }
}