#include <algorithm>
#include <cstdio>
#include <iostream>
#include <queue>
#include <utility>

using namespace std;

int n;
pair<int, int> num[51145];
priority_queue<pair<int, int> > pq;
int res;
int pos[51145];

int main () {

	freopen ("stallreservation.in", "r", stdin);
	freopen ("stallreservation.out", "w", stdout);
	
	cin >> n;
	for (int i = 1; i <= n; i++) {
	    cin >> num[i].first >> num[i].second;
    }
    sort (num + 1, num + 1 + n);
    
    for (int i = 1; i <= n; i++) {
        if (pq.empty() || -pq.top().first > num[i].first) {
            res++;
            pq.push(make_pair (-num[i].second, res));
            pos[i] = res;
        }
        else {
            int id = pq.top().second;
            pq.pop();
            pq.push(make_pair (-num[i].second, id));
            pos[i] = id;
        }
    }
    
    cout << res << endl;
    for (int i = 1; i <= n; i++) {
        cout << pos[i] << endl;
    }

	return 0;
}