#include<iostream>
#include<algorithm>
using namespace std;
struct cow{
	long long a,b,c,id;
}cows[50009];
bool cmp(cow c,cow d)
{
	return c.a<d.a;
}
long long s[50009]={0},ans=0,out[50009];
int main()
{
	long long n;
	cin>>n;
	for (int i=1;i<=n;i++)
	{
		cin>>cows[i].a>>cows[i].b;
		cows[i].c=0;
		cows[i].id=i;
	}
	sort(cows+1,cows+n+1,cmp);
	for (int i=1;i<=n;i++)
	{
		for (int j=1;j<=ans;j++)
		{
			if (s[j]<cows[i].a)
			{
				s[j]=cows[i].b;
				cows[i].c=j;
				out[cows[i].id]=cows[i].c;
				break;
			}
		}
		if (cows[i].c==0)
		{
			ans++;
			s[ans]=cows[i].b;
			cows[i].c=ans;
			out[cows[i].id]=cows[i].c;
		}
	}
	cout<<ans<<endl;
	for (int i=1;i<=n;i++)
	{
		cout<<out[i]<<endl;
	}
	return 0;
}

https://www.luogu.com.cn/record/97768119