#include <bits/stdc++.h>

// #undef DEBUG  // Uncomment this line to forcefully disable debug print.
#if DEBUG
template <typename T>
void debug(const T& value) {
  std::cerr << value;
}
template <typename T, typename... Ts>
void debug(const T& value, const Ts&... args) {
  std::cerr << value << ", ";
  debug(args...);
}
#define dbg(...)                        \
  do {                                  \
    cerr << #__VA_ARGS__ << ": ";       \
    debug(__VA_ARGS__);                 \
    cerr << " (L" << __LINE__ << ")\n"; \
  } while (0)
#else
#define dbg(...)
#endif

void read_from_cin() {}
template <typename T, typename... Ts>
void read_from_cin(T& value, Ts&... args) {
  std::cin >> value;
  read_from_cin(args...);
}
#define in(type, ...) \
  type __VA_ARGS__;   \
  read_from_cin(__VA_ARGS__);

template <typename T>
void write_to_cout(const T& value) {
  std::cout << value << '\n';
}
template <typename T, typename... Ts>
void write_to_cout(const T& value, const Ts&... args) {
  std::cout << value << ' ';
  write_to_cout(args...);
}
#define out(...) write_to_cout(__VA_ARGS__);

#define all(x) (x).begin(), (x).end()
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)

using ll = long long;

template <typename T>
using V = std::vector<T>;
template <typename T>
using VV = V<V<T>>;

using namespace std;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);

  in(int, N, M, Q);

  VV<int> trains(N + 1, V<int>(N + 1));
  rep(i, M) {
    in(int, L, R);
    trains[L][R]++;
  }

  VV<int> sum(N + 2, V<int>(N + 2));
  for (int l = N; l >= 1; --l) {
    for (int r = 1; r <= N; ++r) {
      sum[l][r] =
          sum[l + 1][r] + sum[l][r - 1] - sum[l + 1][r - 1] + trains[l][r];
    }
  }

  rep(i, Q) {
    in(int, p, q);
    out(sum[p][q]);
  }
}

#include "bits/stdc++.h"

using namespace std;

void Main() {
    int N, M, Q;
    cin >> N >> M >> Q;
    vector<map<int, int>> start_length(N, map<int, int>());
    for (int i = 0; i < M; ++i) {
        int l, r;
        cin >> l >> r;
        --l;
        --r;
        if (start_length[l].count(r - l) == 0) {
            start_length[l].insert(make_pair(r - l, 0));
        }
        start_length[l][r - l] += 1;
    }
    vector<vector<int>> start_lengthLess(N, vector<int>());
    for (int i = 0; i < N; ++i) {
        const map<int, int>& length_num = start_length[i];
        vector<int> length(N + 1, 0);
        for (auto e : length_num) {
            length[e.first] = e.second;
        }
        vector<int> accumLength(N + 1, 0);
        accumLength[0] = length[0];
        for (int j = 1; j < accumLength.size(); ++j) {
            accumLength[j] = accumLength[j - 1] + length[j];
        }
        start_lengthLess[i] = accumLength;
    }

    for (int i = 0; i < Q; ++i) {
        int p, q;
        cin >> p >> q;
        --p;
        --q;
        int ans = 0;
        for (int j = p; j <= q; ++j) {
            ans += start_lengthLess[j][q - j];
        }
        cout << ans << endl;
    }
}

int main() {
    std::cout << std::fixed << std::setprecision(15);
    Main();
    return 0;
}
