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<vector>
// #include<algorithm>
// #include<map>
// #include<cstring>
// #include<math.h>
// #include<bitset>
// #include<queue>
// #include<set>
// #include<iomanip>
// #include<math.h>
// #include<assert.h>
// #include<string>
// #include<cstdlib>
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
constexpr ll INF = 1LL << 40;
const double INFD = 1e100;
const ll mod = 1000000007;
const double PI = 3.1415926535897932384626433832795028841971;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
// ----------------------------------------------------------------------------


int main(){
  int N,M,Q;
  cin >> N >> M >> Q;
  vector<int> L(200010),R(200010);
  vector<vector<int>> X(509, vector<int> (509,0));
  vector<vector<int>> C(509, vector<int> (509,0));
  for(int i=1; i<=M; i++){
    cin >> L[i] >> R[i];
    X[L[i]][R[i]]++;
  }
  for(int i=1; i<=N; i++){
    for(int j=1; j<=N; j++){
      C[i][j] = C[i][j-1] + X[i][j];
    }
  }
  for(int i=1; i<=Q; i++){
    int p,q;
    cin >> p >> q;
    int sum=0;
    for(int j=p; j<=q; j++){
      sum += C[j][q] - C[j][p-1];
    }
    cout << sum << endl;
  }
  return 0;
}