#ifndef ONLINE_JUDGE #define _GLIBCXX_DEBUG #endif #include #include #include using namespace std; using namespace atcoder; using ll = long long; using mint = modint998244353; //using mint = modint1000000007; #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define repu(i, s, t) for (int i = (int)(s); i < (int)(t); i++) #define repd(i, s, t) for (int i = (int)(s)-1; i >= (int)(t); i--) #define all(v) v.begin(), v.end() void _u() { cerr << endl; } template void _u(H&& h, T&&... t) { cerr << h << ", "; _u(move(t)...); } #define U(...) { cerr << #__VA_ARGS__ << ": "; _u(__VA_ARGS__); } template bool chmax(T &a, const T b) { if(a >= b) return false; a = b; return true; } template bool chmin(T &a, const T b) { if(a <= b) return false; a = b; return true; } template istream& operator>>(istream &in, vector &a) { for(T &x: a) in >> x; return in; } template ostream& operator<<(ostream &out, const vector &a) { for(const T &x: a) out << x << ' '; return out; } const int di[] = {1, 0, -1, 0, 1, 1, -1, -1, 0}; const int dj[] = {0, 1, 0, -1, -1, 1, 1, -1, 0}; template struct CC { bool initialized; vector xs; CC(): initialized(false) {} void add(T x) { xs.push_back(x); } void init() { sort(xs.begin(), xs.end()); xs.erase(unique(xs.begin(), xs.end()), xs.end()); initialized = true; } int operator()(T x) { if(!initialized) init(); return lower_bound(xs.begin(), xs.end(), x) - xs.begin(); } T operator[](int i) { if(!initialized) init(); return xs[i]; } int size() { if(!initialized) init(); return xs.size(); } }; const ll INF = 1e18; using S = ll; S op(S l, S r) { return max(l, r); } S e() { return -INF; } using F = ll; S mapping(F l, S r) { return l + r; } F composition(F l, F r) { return l + r; } F id() { return 0; } int main() { int n, a; cin >> n >> a; a++; CC cc; vector> qs; rep(i, n) { int x, y, v; cin >> x >> y >> v; cc.add(y), cc.add(y+a); qs.emplace_back(x, 1, y, v); qs.emplace_back(x+a, -1, y, v); } lazy_segtree lst(vector(cc.size()*2, 0LL)); ll ans = 0; sort(all(qs)); ll prem = -INF, prep = -INF; for(auto[x, t, y, v]: qs) { if(t < 0 && x != prem) { chmax(ans, lst.all_prod()); prem = x; } if(t > 0 && x != prep) { chmax(ans, lst.all_prod()); prep = x; } lst.apply(cc(y)*2, cc(y+a)*2-1, v*t); } cout << ans << endl; return 0; }