#include <bits/stdc++.h>
using namespace std;


using ll = long long;
using ull = unsigned long long;
using ld = long double;
using vll = vector<ll>;
using pll = pair<ll, ll>;
using mll = map<ll,ll>;
using sll = set<ll>;
#define iv(v) for(auto &i:v) cin >> i
#define ov(v) for(auto &i:v) cout << i << " "
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define YES cout << "YES\n"
#define NO  cout << "NO\n"

#define Bismillah ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);

const ll MOD = 1e9 + 7;

ll add(ll a, ll b) {return ((a % MOD) + (b % MOD)) % MOD;}
ll mul(ll a, ll b) {return ((a % MOD) * (b % MOD)) % MOD;}
ll sub(ll a, ll b) {return (((a - b) % MOD) + MOD) % MOD;}
ll modExp(ll a, ll b) {
    if (b <= 0) return 1;
    ll ret = modExp(a * a % MOD, b / 2);
    if (b % 2) ret = ret * a % MOD;
    return ret;
}
ll inverse(ll b) {return modExp(b, MOD - 2);}
ll divv(ll a, ll b) {return ((a % MOD) * (inverse(b) % MOD)) % MOD;}



void solve() {
    ll n;
    cin >> n;
    vector<pair<ll,ll>>v(n);
    ll rn=1;
    set<pair<ll,ll>>s;
    vll m(n);
    for (int i=0; i<n; i++) {

        cin >> v[i].first >> v[i].second;
    }
    sort(all(v));
    for (int i=0; i<n; i++) {
        if (s.empty() || s.begin()->first>=v[i].first) {
            m[i]=rn;
            s.insert({v[i].second,rn});
            rn++;
        }
        else {
            m[i]=s.begin()->second;
            s.erase(s.begin());
            s.insert({v[i].second,m[i]});
        }

    }
    cout << rn-1 << endl;
    ov(m);
}

int main() {
    Bismillah
    ll t=1;
//    cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}