// Berlet.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <queue>

#define ll long long
using namespace std;

ll n, m;
int main()
{
	cin >> n >> m;
	vector<pair<ll,ll>>x(m + 1);
	vector<ll>ans;
	for (int i = 1; i <= n; ++i)
	{
		//ll a, b;
		cin >> x[i].first >> x[i].second;
	
	}
	int i = 1, veg = 1;
	while (veg<m)
	{
		ll akt = -1;
		while (i <= n && x[i].first <= veg)
		{
			if (akt == -1 || x[i].second > x[akt].second)
			{
				akt = i;
				
			}
			++i;
		}
		
		if (akt == -1)
		{
			cout<<"-1";
			return 0;
		}
		else
		{
			veg = x[akt].second;
			ans.push_back(akt);
		}

	}
	cout << ans.size() - 1<<"\n";
	for (auto& e : ans)cout << e << " ";
   return 0;
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file