#include <bits/stdc++.h>
using namespace std;
int a[200002];
int b[200002];
int ans[200002];
int main() {
  int n, m, l;
  cin >> n >> m >> l;
  pair<int, int> q[n];
  for (int i = 0; i < n; i++) {
    cin >> q[i].first >> q[i].second;
    a[q[i].first]++;
    a[q[i].second + 1]--;
  }
  int s = 0;
  for (int i = 0; i <= 200002; i++) {
    s += a[i];
    b[i] += s;
  }
  s = 0;
  for (int i = 0; i <= 200001; i++) {
    if (b[i] >= m) {
      s++;
    }
    ans[i] = s;
  }
  for (int i = 0; i < l; i++) {
    int x, y;
    cin >> x >> y;
    cout << ans[y] - ans[x - 1] << endl;
  }
}
