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 JavaScript (node.js v5.12) (judge verdict: Accepted)

function Main(s){
  s = s.split("\n");
  var n = s[0].split(" ").map(a=>+a);
  var m = n[1], q = n[2]; n = n[0];
  var a = Array(n+1).fill(0).map(a=>[]);
  for(var i = 0; i < m; i++){
    var l = s[i+1].split(" ").map(a=>+a);
    a[l[0]].push(l[1])
  }
  for(i = 1; i <= n; i++)a[i].sort((a,b)=>a-b);
  var ans = [];
  for(i = 0; i < q; i++){
    var p = s[i+m+1].split(" ").map(a=>+a);
    var t = 0;
    for(j = p[0]; j <= p[1]; j++){
      t += upper_bound(a[j], 0, a[j].length, p[1])
    }
    ans[i] = t;
  }
  console.log(ans.join("\n"));
}
function upper_bound(d,a,b,e){for(var c;1<b-a;)d[c=0|(a+b)/2]<=e?a=c:b=c;return d[a]<=e?b:a};
Main(require("fs").readFileSync("/dev/stdin","utf8"));