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)


import numpy as np
import sys
sys.setrecursionlimit(100000)



def acinput():
    return list(map(int, input().split(" ")))



directions=np.array([[1,0],[0,1],[-1,0],[0,-1]])
directions = list(map(np.array, directions))

mod = 10**9+7


def factorial(n):
    fact = 1
    for integer in range(1, n + 1):
        fact *= integer
    return fact



def serch(x, count):
    #print("top", x, count)
            

    for d in directions:
        nx = d+x
        #print(nx)
        if np.all(0 <= nx) and np.all(nx < (H, W)):
            if field[nx[0]][nx[1]] == "E":
                count += 1 
                field[nx[0]][nx[1]] = "V"
                count = serch(nx, count)  
                continue
            if field[nx[0]][nx[1]] == "#":
                field[nx[0]][nx[1]] = "V"
                count = serch(nx, count)    
                 
    return count

N,M,Q=acinput()

A=np.zeros([N+1,N+1])

for i in range(M):
    tmp=acinput()
    A[tmp[0],tmp[1]]+=1
Acs=np.cumsum(A,axis=1 )
Acs=np.cumsum(Acs,axis=0)

for i in range(Q):
    tmp=acinput()
    print(int(Acs[tmp[1], tmp[1]]-Acs[tmp[1],tmp[0]-1]-Acs[tmp[0]-1,tmp[1]]+Acs[tmp[0]-1, tmp[0]-1]))