---

#include <iostream>
#include <vector>
#include <utility>
#include <algorithm>
#include <cmath>
#include <iterator>
#include <string>
#include <iomanip>
//#include <bits/stdc++.h>
using namespace std;
#define fr first
#define sc second
#define all(v) v.begin(),v.end()
#define vpii vector <pair<int,int> >
#define CIN ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL)
#define Unique(x)  x.erase(unique(all(x)), x.end())
#define Read() freopen("input.cpp", "r", stdin)
#define Write() freopen("output.cpp", "w", stdout)
#define FOR(q,w,e) for(q=w;q<e;q++)
#define endl "\n"
#define ll long long
int main()
{
	int n,x,key,mid,lt,rt;
	long long j = 0;
	int konec,i;
    ios_base::sync_with_stdio(false) ; cin.tie(NULL) ; cout.tie(NULL);
	cin >> n >> x;
    vector < pair < pair < int,long long > ,pair < int,int > > > b(n);
    for(i = 0 ; i < n ; i ++ )
    {
   	   cin >> b[i].second.first >> b[i].second.second >> b[i].first.second;
   	   b[i].first.first = b[i].second.second - b[i].second.first + 1;
    }
   	sort(b.begin(),b.end());
    if(x % 2 == 0) j = x / 2;
    else j = x / 2 + 1;
    if(b[0].first.first > j)
    {
        cout << - 1;
        return 0;
    }
    j = 0;
    key = 0;
    vector < pair < pair < int,long long > ,pair < int,int > > > a (n);
    vector < pair < pair < int,long long > ,pair < int,int > > > c (n);
    for(i = 0 ; i < n && b[i].first.first < x ; i ++ )
    {
    	while(i < n - 1 && b[i].first.second == b[i + 1].first.second && b[i].second.first == b[i + 1].second.first && b[i].second.second == b[i + 1].second.second)
    	{
    		 i ++ ;
        }
        if(x % 2 != 0 || b[i].first.first != x / 2)
    	{
        a[j].first.first = b[i].first.first;
        a[j].first.second = b[i].first.second;
        a[j].second.second = b[i].second.second;
        a[j].second.first = b[i].second.first;
    		j ++ ;
    	}
    	else
    	{
         c[key].first.first = b[i].first.first;
         c[key].first.second = b[i].first.second;
         c[key].second.second = b[i].second.second;
         c[key].second.first = b[i].second.first;
         key ++ ; 
        }	 
        // cout << "i=" << i << " j=" << j << "\n";
    }
    // cout << "i=" << i << " j=" << j << "\n";
    a.resize(j);
    c.resize(key);
    konec = j;
    if(x % 2 == 0) j = x / 2;
    if(a[a.size() - 1].first.first == x / 2) konec = a.size();
    else
    {  
   	for(i = 0 ; i < a.size() ; i ++ )
    {
        if(a[i].first.first > j)
        {
        	konec = i;
        	break;
        }
    }
    }
    /* 
    cout << "b= \n";
    for(i = 0 ; i < n ; i ++ )
    {
    	cout << b[i].first.first << " " << b[i].first.second << " " << b[i].second.first << " " << b[i].second.second << "\n";
    }
    cout << "a= \n";
    for(i = 0 ; i < a.size() ; i ++ )
    {
    	cout << a[i].first.first << " " << a[i].first.second << " " << a[i].second.first << " " << a[i].second.second << "\n";
    }
    cout << "c= \n";
    for(i = 0 ; i < c.size() ; i ++ )
    {
    	cout << c[i].first.first << " " << c[i].first.second << " " << c[i].second.first << " " << c[i].second.second << "\n";
    }
        
    cout << "konec=" << konec << "\n";
    */ 
    long long f = 3e9;
    for(i = 0 ; i < c.size() && c[i].first.second < f ; i ++ )
    {
    	j = i + 1;
    	while(j < c.size() && f > c[j].first.second + c[i].first.second)
    	{
    		 // cout << "j=" << j << " ";
    		if(c[i].second.second < c[j].second.first || c[i].second.first > c[j].second.second)
    		{
    			f = c[j].first.second + c[i].first.second;
    			break;
    		}
    		j ++ ;
    	}
    	 // cout << "\n";
    }		
	int oper;
   	for(i = 0 ; i < konec ; i ++ ) // ?? ????? ??? ?? konec
   	{
   		if(a[i].first.second < f)
   		{
		if(a[i].first.first != a[i - 1].first.first)
		{
   		 // cout << i << " ";
   	    j = i;
   		lt = j + 1;
   		rt = a.size() - 1;
   		key = x - a[j].first.first;
   		while(lt < rt && key < a[rt].first.first && key >= a[lt].first.first)
   		{
   			mid = (lt + rt) / 2 ;   			
            if(key < a[mid].first.first)
            {
                rt = mid - 1;
            }
            else
            {
                if(key == a[mid].first.first)
                {
                    rt = mid;
                }
                else
                {
                  lt = mid + 1;
                }
            }
        }
        // cout << "rt=" << rt << "\n";
        j = rt;
        if(key == a[j].first.first)
        {
        	 // prover r and l
            if(f > a[j].first.second + a[i].first.second && (a[j].second.second < a[i].second.first || a[j].second.first > a[i].second.second))
            {
                f = a[j].first.second + a[i].first.second;
                // cout << "f=" << f << "\n";
            }
            while(j > 0 && a[j].first.first == a[j - 1].first.first)
            {
            	j -- ;
            }
			oper = j;
            // cout << "oper=" << oper << "\n";
            while(a[j].first.first == key && j < a.size() && a[j].first.second + a[i].first.second < f)
            {
 				if(a[i].second.second < a[j].second.first || a[i].second.first > a[j].second.second)
                {
                        f = a[j].first.second + a[i].first.second;
                        break;
                }
                j ++ ;
             }     	
        }
		}
		else
		{
			j = oper;
            while(a[j].first.first == key && j < a.size() && a[j].first.second + a[i].first.second < f)
            {
 				if(a[i].second.second < a[j].second.first || a[i].second.first > a[j].second.second)
                {
                        f = a[j].first.second + a[i].first.second;
                        break;
                }
                j ++ ;
             }   		
		}
		}
    }
    if(f != 3e9)
    {
        cout << f;
    }
    else
    {
        cout << - 1;
    }
    /* 
    https: // codeforces.com / contest / 822 / submission / 66507075
4 3
1 1 2
1 1 3
2 3 3
2 3 4
    */ 
}