#include <bits/stdc++.h> using namespace std; #define int long long #define rep(x, a, b) for(auto x=a;(a<b?x<b:x>b);(a<b?x++:x--)) #define all(a) a.begin(), a.end() #define srtvc(a) sort(all(a)) #define bcsrtvc(a) sort(all(a), greater<__typeof__(a[0])>()) #define ppf pop_front #define ppb pop_back #define pf push_front #define pb push_back #define ef emplace_front #define eb emplace_back #define fr first #define sc second #define pq priority_queue #define pii pair<int, int> #define vc vector #define dq deque #define sz(a) a.size() #define mnto(x,y) x = min(x, (__typeof__(x))y) #define mxto(x,y) x = max(x, (__typeof__(x))y) #define setval(arr, x) memset(arr, x, sizeof(arr)) template<typename T> using vv = vc<vc<T>>; const int MAXN = 3e5+5; int arr[MAXN]; struct SegTree { struct Node { int l, r, mid; int val = 0, lz = 0; Node *L = nullptr, *R = nullptr; Node(int _l, int _r) : l(_l), r(_r) { mid = (l + r) >> 1; if (l != r) { L = new Node(l, mid); R = new Node(mid+1, r); } } void apply(int v) { val += v; lz += v; } void push() { if (lz == 0 || l == r) return; L->apply(lz); R->apply(lz); lz = 0; } void pull() { val = min(L->val, R->val); } void build() { if (l == r) { val = arr[l]; return; } L->build(); R->build(); pull(); } void update(int ql, int qr, int v) { if (qr < l || r < ql) return; if (ql <= l && r <= qr) { apply(v); return; } push(); L->update(ql, qr, v); R->update(ql, qr, v); pull(); } int qryMin() { return val; } }; Node* root; int n; SegTree(int _n) : n(_n) { root = new Node(0, n-1); } void build() { root->build(); } void update(int l, int r, int v) { root->update(l, r, v); } int qry() { return -root->qryMin(); } }; int32_t main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n, d; cin >> n >> d; tuple<int, int, int> st[n]; rep(i, 0, n) { int x, a, b; cin >> x >> a >> b; st[i] = {x, a, b}; } sort(st, st+n); rep(i, 0, n) { auto [x, a, b] = st[i]; arr[i] = -x; st[i] = {b, a, i}; } arr[n] = -d; sort(st, st+n, greater<>()); SegTree seg(MAXN); seg.build(); int mn = seg.qry(); rep(i, 0, n) { auto [b, a, ix] = st[i]; seg.update(ix+1, n, a); if (b >= seg.qry()) mnto(mn, seg.qry()); } cout << mn; }