// A lehető legkevesebb átszállá.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <vector>
using namespace std;
int jok[100001]{ 0 };
int main()
{
    int n, m, kezd, veg, hol = 1, hova = 0, jo, valami=0,max=0,z=1,db=0,t=1,ln=0;
    cin >> n >> m;
    int tombkezd[100001]{ 0 };
    int tombveg[100001]{ 0 };
    //int jok[100001]{ 0 };
    for (int i = 1; i <= n; i++) 
    {
        cin >> kezd >> veg;
        tombkezd[i] = kezd;
        tombveg[i] = veg;
        if (veg > ln) {
            ln = veg;
        }
    }
    if (ln < m) {
        cout << "-1";
    }
    while (hol < m) 
    {   
        valami = 0;
        for (int i = 1; i <= n; i++) {
            if (tombkezd[i] == hol and tombveg[i]>hova) {
                valami = 1;
                hova = tombveg[i];
                jo = i;
            }
        }
        hol = hova;
        if (hova == max) {
            valami = 0;
        }
        if (hol > max) { 
            max=hol;
        }
        
        if (valami == 0 or hol<max) {
            hol=max-z;
            hova=max-z;
            z++;
            //cout << hol;
        }
        if (valami == 1) {
            jok[t] = jo;
            t++;
            z = 1;
        }
    }
    cout << t - 2<<endl;
    for (int alma = 1; alma <= t - 1; alma++) {
        cout << jok[alma] << " ";
    }

}

// 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