#include using namespace std; using ll = long long; template struct segtree { public: segtree() : segtree(0) {} segtree(int n) : segtree(std::vector(n, e())) {} segtree(const std::vector& v) : _n(int(v.size())) { log = ceil_pow2(_n); size = 1 << log; d = std::vector(2 * size, e()); for (int i = 0; i < _n; i++) d[size + i] = v[i]; for (int i = size - 1; i >= 1; i--) { update(i); } } void set(int p, S x) { assert(0 <= p && p < _n); p += size; d[p] = x; for (int i = 1; i <= log; i++) update(p >> i); } S get(int p) { assert(0 <= p && p < _n); return d[p + size]; } const S operator[](int p) const { return get(p); } S operator[](int p) { return get(p); } S prod(int l, int r) { assert(0 <= l && l <= r && r <= _n); S sml = e(), smr = e(); l += size; r += size; while (l < r) { if (l & 1) sml = op(sml, d[l++]); if (r & 1) smr = op(d[--r], smr); l >>= 1; r >>= 1; } return op(sml, smr); } S all_prod() { return d[1]; } template int max_right(int l) { return max_right(l, [](S x) { return f(x); }); } template int max_right(int l, F f) { assert(0 <= l && l <= _n); assert(f(e())); if (l == _n) return _n; l += size; S sm = e(); do { while (l % 2 == 0) l >>= 1; if (!f(op(sm, d[l]))) { while (l < size) { l = (2 * l); if (f(op(sm, d[l]))) { sm = op(sm, d[l]); l++; } } return l - size; } sm = op(sm, d[l]); l++; } while ((l & -l) != l); return _n; } template int min_left(int r) { return min_left(r, [](S x) { return f(x); }); } template int min_left(int r, F f) { assert(0 <= r && r <= _n); assert(f(e())); if (r == 0) return 0; r += size; S sm = e(); do { r--; while (r > 1 && (r % 2)) r >>= 1; if (!f(op(d[r], sm))) { while (r < size) { r = (2 * r + 1); if (f(op(d[r], sm))) { sm = op(d[r], sm); r--; } } return r + 1 - size; } sm = op(d[r], sm); } while ((r & -r) != r); return 0; } private: int _n, size, log; std::vector d; int ceil_pow2(int n) { int x = 0; while ((1U << x) < (unsigned int)(n)) x++; return x; } void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); } }; ll op(ll lhs, ll rhs){return max(lhs, rhs);} ll e(){return 0;} int main(){ ios::sync_with_stdio(false); cin.tie(0); int n, x, y, z; cin >> n; vector> a(n); vector cb(n); for(int i = 0; i < n; i++){ cin >> x >> y >> z; a[i] = make_tuple(x, y, z); cb[i] = y; } sort(cb.begin(), cb.end()); cb.erase(unique(cb.begin(), cb.end()), cb.end()); sort(a.begin(), a.end(), [&](tuple lhs, tuple rhs){ return make_pair(get<0>(lhs), -get<1>(lhs)) < make_pair(get<0>(rhs), -get<1>(rhs)); }); segtree seg(cb.size()); for(int i = 0; i < n; i++){ tie(x, y, z) = a[i]; y = lower_bound(cb.begin(), cb.end(), y) - cb.begin(); ll v = seg.prod(0, y); seg.set(y, max(seg[y], v + z)); } cout << seg.all_prod() << '\n'; }