#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second

class Solution
{
    static bool comp(vector<int>& v1, vector<int>& v2)
    {
        if (v1[1] == v2[1])
            return v1[0] < v2[0];
        return v1[1] < v2[1];
    }
public:
    int eraseOverlapIntervals(vector<vector<int>>& intervals)
    {
        vector<vector<int>> r;
        int sz = intervals.size();
        sort(intervals.begin(), intervals.end(), comp);
        auto aux = intervals[0];
        int ans = 1;
        for (int i = 1; i < intervals.size(); i++)
        {
            if (intervals[i][0] > aux[1])
            {
                ans++;
                aux = intervals[i];
            } else {
                intervals.erase(intervals.begin() + i);
                i--;
            }
        }
        return sz - ans;
    }
};

signed main()
{
    int n;
    cin >> n;
    vector<vector<int>> segs(n, vector<int>(2));
    for (auto &it : segs)
    {
        cin >> it[0] >> it[1];
    }
    Solution s;
    int e = s.eraseOverlapIntervals(segs);
    cout << "erased:" << e << endl;
    for (const auto &it : segs)
    {
        cout << it[0] << ' ' << it[1] << endl;
    }
    return 0;
}