#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <queue>
#include <deque>
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;
#define REP(i,a,b) for(ll i=a; i<b; i++)
#define pb push_back
#define mp make_pair
#define pl pair<ll,ll>
#define ff first
#define ss second
#define INF 100000000000000000LL
ll insig;
#define In(vecBRO, LENBRO) REP(IBRO,0,LENBRO) {cin>>insig; vecBRO.pb(insig);}
void Out(vector<ll> x) {REP(i,0,x.size()) {cout<<x[i]<<" ";} cout<<endl;}
class ST
{
public:
ll N;
class SV //seg value
{
public:
ll a;
SV() {a=-INF;}
SV(ll x) {a=x;}
};
class LV //lazy value
{
public:
ll a;
LV() {a=0LL;}
LV(ll x) {a=x;}
};
SV op(SV A, SV B) //how seg values interact
{
SV X(max(A.a,B.a));
return X;
}
SV upval(ll c, ll x, ll y) //how lazy values modify a seg value, c=current node ,[x,y]=interval acting
{
SV X(p[c].a+lazy[c].a);
return X;
}
LV inter(LV A,LV B) //how lazy values interact
{
LV X(A.a+B.a);
return X;
}
SV neuts; LV neutl;
vector<SV> ar; vector<SV> p;
vector<LV> lazy;
ST(vector<ll> arr)
{
N = (ll) 1<<(ll) ceil(log2(arr.size()));
REP(i,0,arr.size()) {SV X(arr[i]); ar.pb(X);}
REP(i,arr.size(),N) {ar.pb(neuts);}
REP(i,0,N) {p.pb(neuts);}
REP(i,0,N) {p.pb(ar[i]);}
ll cur = N-1;
while(cur>0)
{
p[cur]=op(p[2*cur],p[2*cur+1]);
cur--;
}
REP(i,0,2*N) {lazy.pb(neutl);}
}
void prop(ll c, ll x, ll y) //how lazy values propagate
{
p[c]=upval(c,x,y);
lazy[2*c]=inter(lazy[c],lazy[2*c]); lazy[2*c+1]=inter(lazy[c],lazy[2*c+1]);
lazy[c]=neutl;
if(2*c>=N)
{
p[2*c]=upval(2*c,2*c,2*c); p[2*c+1]=upval(2*c+1,2*c+1,2*c+1);
ar[2*c-N]=p[2*c];
ar[2*c+1-N]=p[2*c+1];
lazy[2*c]=neutl; lazy[2*c+1]=neutl;
}
}
SV query(ll a,ll b, ll c, ll x, ll y) //c=current node, starting in 1, a,b=range of query, x,y=range of node c in the array down, x,y from 0 to N-1. query(a,b)->query(a,b,1,0,N-1)
{
if(y<a || x>b) {return neuts;}
if(x>=a && y<=b) {return upval(c,x,y);}
prop(c,x,y);
ll mid=(x+y)/2;
SV ans = op(query(a,b,2*c,x,mid),query(a,b,2*c+1,mid+1,y));
return ans;
}
void update(LV s, ll a, ll b, ll c, ll x, ll y) //positions in [a,b] from 0 to N-1 gets +s
{
if(y<a || x>b) {return ;}
if(x>=a && y<=b)
{
lazy[c]=inter(s,lazy[c]);
if(c>=N) {p[c]=upval(c,c,c); lazy[c]=neutl; ar[c-N]=p[c];}
return;
}
ll mid=(x+y)/2;
update(s,a,b,2*c,x,mid); update(s,a,b,2*c+1,mid+1,y);
p[c]=op(upval(2*c,x,mid),upval(2*c+1,mid+1,y));
}
};
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
ll N,D; cin>>N>>D; vector<ll> xx; xx.pb(0LL); xx.pb(0LL); xx.pb(0LL); vector<vector<ll> > Sta;
REP(i,0,N) {cin>>xx[0]>>xx[1]>>xx[2]; Sta.pb(xx);}
sort(Sta.begin(),Sta.end());
vector<ll> X,A,B; REP(i,0,N) {X.pb(Sta[i][0]); A.pb(Sta[i][1]); B.pb(Sta[i][2]);}
map<ll,vector<ll> > m;
REP(i,0,N)
{
m[B[i]].pb(i);
}
set<ll> bvals; REP(i,0,N) {bvals.insert(B[i]);}
vector<ll> Sbeg; ll psA=0LL;
REP(i,0,N) {Sbeg.pb(X[i]-psA); psA+=A[i];}
Sbeg.pb(D-psA);
ST S(Sbeg);
set<ll>::iterator it=bvals.begin();
ll ans=D;
while(it!=bvals.end())
{
if(it!=bvals.begin())
{
it--;
REP(i,0,m[*it].size())
{
ll ind=m[*it][i];
ST::LV U(A[ind]);
S.update(U,ind+1LL,S.N-1,1LL,0LL,S.N-1LL);
}
it++;
}
ll curans=S.query(0LL,S.N-1,1,0,S.N-1).a;
if(curans<=*it) {ans=min(ans,curans);}
it++;
}
cout<<ans<<endl;
return 0;
}
