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: Time Limit Exceeded)

#include<bits/stdc++.h> 
using namespace std;
using ll=long long;
typedef pair<int,int> P;
#define fi first
#define se second
#define all(v) (v).begin(),v.end()
set<string> c;
const ll mod=1000000007;
const ll mod2=998244353;
const ll inf=100000000000000000;
ll gcd(ll a,ll b) {return b ? gcd(b,a%b):a;}
ll lcm(ll c,ll d){return c/gcd(c,d)*d;}
vector<int> dy={-1,0,1,0},dx={0,-1,0,1};
map<char,ll> mp;
int main(){
int n,m,q;
cin>>n>>m>>q;
vector<vector<int>>root(n,vector<int>(n,0));
for(int i=0;i<m;i++){
    int a,b;
    cin>>a>>b;
    a--;b--;
    root.at(a).at(b)++;
}
vector<int> ans;
for(int t=0;t<q;t++){
int l,r;
cin>>l>>r;
l--;r--;
int res=0;
for(int i=l;i<=r;i++){
for(int j=l;j<=r;j++){
    res+=root.at(i).at(j);
}
}
ans.push_back(res);
}
for(int i=0;i<ans.size();i++)cout<<ans.at(i)<<endl;
}