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 Python (3.4.3) (judge verdict: Accepted)

# https://atcoder.jp/contests/abc106/tasks/abc106_d
# 何も見ずにやり直してみる

import sys
sys.setrecursionlimit(1 << 25)
read = sys.stdin.readline


def read_ints():
    return list(map(int, read().split()))


N, M, Q = read_ints()

# 列車を二次元座標に代入
table = [[0] * N for _ in range(N)]  # 都市はそれぞれ-1扱い
for _ in range(M):
    L, R = read_ints()
    table[L - 1][R - 1] += 1

# 二次元累積和を取る
import numpy as np
table_ = np.array(table)
table = np.zeros((N + 1, N + 1), dtype='int')
table[1:, 1:] = table_.cumsum(axis=0).cumsum(axis=1)
# print(table)

# クエリに答える
for _ in range(Q):
    p, q = read_ints()
    print(table[q, q] - table[p - 1, q] -
          table[q, p - 1] + table[p - 1, p - 1])