#include <iostream>
#include <algorithm>
#include <map>
#define ll long long
#define pii pair<int, int>
#define ppi pair<pii, int>
#define fst first
#define snd second
using namespace std;
const int SZ = (1 << 20) + 69;
int n, d;
ll coord[300069] = {}, seg[SZ] = {}, lz[SZ], rs = 1e18;
map<int, int> mp;
ppi dt[300069] = {};
void bld(int idx, int L, int R)
{
if (L < R)
{
bld(2 * idx, L, (L + R) / 2);
bld(2 * idx + 1, (L + R) / 2 + 1, R);
seg[idx] = max(seg[2 * idx], seg[2 * idx + 1]);
}
else {seg[idx] = coord[L];}
}
void prop(int idx, int L, int R)
{
if (lz[idx])
{
seg[idx] += lz[idx];
if (L < R)
{
lz[2 * idx] += lz[idx];
lz[2 * idx + 1] += lz[idx];
}
lz[idx] = 0;
}
}
void upd(int idx, int L, int R, int x, int v)
{
prop(idx, L, R);
if (x <= R)
{
if (x <= L) {lz[idx] += v; prop(idx, L, R);}
else
{
int M = (L + R) / 2;
upd(2 * idx, L, M, x, v);
upd(2 * idx + 1, M + 1, R, x, v);
seg[idx] = max(seg[2 * idx], seg[2 * idx + 1]);
}
}
}
int main()
{
ios :: sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> d;
rs = d;
for (int i = 0; i < n; i++)
{
int x, a, b; cin >> x >> a >> b;
mp[x] = 1;
dt[i] = {{b, x}, a};
}
mp[d] = 1;
int it = 0;
for (auto &x : mp)
{
coord[it] = x.fst;
x.snd = it++;
}
bld(1, 0, it - 1);
//cout << seg[1] << "\n";
for (int i = 0; i < n; i++)
{
upd(1, 0, it - 1, mp[dt[i].fst.snd] + 1, -dt[i].snd);
}
sort(dt, dt + n);
//cout << seg[1] << "\n";
for (int i = 0; i < n; i++)
{
if (seg[1] <= dt[i].fst.fst) {rs = min(rs, seg[1]);}
upd(1, 0, it - 1, mp[dt[i].fst.snd] + 1, dt[i].snd);
}
cout << rs << "\n";
return 0;
}
