#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <algorithm>
#include <ctype.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stack>
#include <vector>
#include <queue>
#include <set>
#include <math.h>
#include <map>
#include <list>
#include <ctime>
#include <limits>

using namespace std;

typedef pair<int,int> P;
struct Cow{
    P time;
    int id;
    bool operator >(const Cow &b) const{
        return time>b.time;
    }
};


struct Stall{
    int id,last;
    Stall(){
        id=0,last=0;
    }
    Stall(int i,int l){
        id=i,last=l;
    }
    bool operator <(const Stall &b) const{
        return this->last>b.last;
    }
};


class Stalls{
public:
    priority_queue <Stall ,vector<Stall> >  stalls;

    int push(const Cow &c){
        int num;
        if(stalls.empty()){
            Stall s(1,c.time.second);
            num=1;
            stalls.push(s);
        }
        else{//先要找出第一个，分可以和不可以两种
            Stall best_one=stalls.top();
            stalls.pop();
            if(best_one.last<c.time.first){
                best_one.last=c.time.second;
                stalls.push(best_one);
                num=best_one.id;
            }
            else{
                stalls.push(best_one);
                num=stalls.size()+1;
                Stall s(num,c.time.second);
                stalls.push(s);
            }
        }
        return num;
    }
};


int main() {
    int n;
    while(scanf("%d",&n)!=EOF) {
        Cow c;
        Stalls ss;
        int *ans=new int[n];
        priority_queue<Cow,vector<Cow> ,greater<Cow> > cows;
        for (int i = 0; i < n; i++) {
            scanf("%d %d",&c.time.first,&c.time.second);
            c.id=i;
            cows.push(c);
        }
        while(cows.empty()==0){
            Cow c =cows.top();
            ans[c.id]=(ss.push(c));
            cows.pop();
        }

        cout << ss.stalls.size() << endl;
        for (int i = 0; i <n; i++) {
            cout << ans[i] << endl;
        }
    }
    return 0;
}