#include <iostream>
#include <vector>
using namespace std;

int main() {
    int N;
    cin >> N;
    vector<pair<int, int>> a(N);
    for (int i = 0; i < N; i++) {
        cin >> a[i].first >> a[i].second;
    }

    int c = 0;
    for (int i = 0; i < N; i++) {
        for (int j = i + 1; j < N; j++) {
            if (a[i].second >= a[j].first && a[i].first <= a[j].second) {
                c++;
            }
        }
    }

    cout << c << endl;
    return 0;
}