#include <bits/stdc++.h> 

using namespace std;

namespace atcoder {

    namespace internal {

        // @param n `0 <= n`
        // @return minimum non-negative `x` s.t. `n <= 2**x`
        int ceil_pow2(int n) {
            int x = 0;
            while ((1U << x) < (unsigned int)(n)) x++;
            return x;
        }

        // @param n `1 <= n`
        // @return minimum non-negative `x` s.t. `(n & (1 << x)) != 0`
        int bsf(unsigned int n) {
#ifdef _MSC_VER
            unsigned long index;
            _BitScanForward(&index, n);
            return index;
#else
            return __builtin_ctz(n);
#endif
        }

    }  // namespace internal

}  // namespace atcoder


namespace atcoder {

    template <class S,
        S(*op)(S, S),
        S(*e)(),
        class F,
        S(*mapping)(F, S),
        F(*composition)(F, F),
        F(*id)()>
        struct lazy_segtree {
        public:
            lazy_segtree() : lazy_segtree(0) {}
            explicit lazy_segtree(int n) : lazy_segtree(std::vector<S>(n, e())) {}
            explicit lazy_segtree(const std::vector<S>& v) : _n(int(v.size())) {
                log = internal::ceil_pow2(_n);
                size = 1 << log;
                d = std::vector<S>(2 * size, e());
                lz = std::vector<F>(size, id());
                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;
                for (int i = log; i >= 1; i--) push(p >> i);
                d[p] = x;
                for (int i = 1; i <= log; i++) update(p >> i);
            }

            S get(int p) {
                assert(0 <= p && p < _n);
                p += size;
                for (int i = log; i >= 1; i--) push(p >> i);
                return d[p];
            }

            S prod(int l, int r) {
                assert(0 <= l && l <= r && r <= _n);
                if (l == r) return e();

                l += size;
                r += size;

                for (int i = log; i >= 1; i--) {
                    if (((l >> i) << i) != l) push(l >> i);
                    if (((r >> i) << i) != r) push((r - 1) >> i);
                }

                S sml = e(), smr = e();
                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]; }

            void apply(int p, F f) {
                assert(0 <= p && p < _n);
                p += size;
                for (int i = log; i >= 1; i--) push(p >> i);
                d[p] = mapping(f, d[p]);
                for (int i = 1; i <= log; i++) update(p >> i);
            }
            void apply(int l, int r, F f) {
                assert(0 <= l && l <= r && r <= _n);
                if (l == r) return;

                l += size;
                r += size;

                for (int i = log; i >= 1; i--) {
                    if (((l >> i) << i) != l) push(l >> i);
                    if (((r >> i) << i) != r) push((r - 1) >> i);
                }

                {
                    int l2 = l, r2 = r;
                    while (l < r) {
                        if (l & 1) all_apply(l++, f);
                        if (r & 1) all_apply(--r, f);
                        l >>= 1;
                        r >>= 1;
                    }
                    l = l2;
                    r = r2;
                }

                for (int i = 1; i <= log; i++) {
                    if (((l >> i) << i) != l) update(l >> i);
                    if (((r >> i) << i) != r) update((r - 1) >> i);
                }
            }

            template <bool (*g)(S)> int max_right(int l) {
                return max_right(l, [](S x) { return g(x); });
            }
            template <class G> int max_right(int l, G g) {
                assert(0 <= l && l <= _n);
                assert(g(e()));
                if (l == _n) return _n;
                l += size;
                for (int i = log; i >= 1; i--) push(l >> i);
                S sm = e();
                do {
                    while (l % 2 == 0) l >>= 1;
                    if (!g(op(sm, d[l]))) {
                        while (l < size) {
                            push(l);
                            l = (2 * l);
                            if (g(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 <bool (*g)(S)> int min_left(int r) {
                return min_left(r, [](S x) { return g(x); });
            }
            template <class G> int min_left(int r, G g) {
                assert(0 <= r && r <= _n);
                assert(g(e()));
                if (r == 0) return 0;
                r += size;
                for (int i = log; i >= 1; i--) push((r - 1) >> i);
                S sm = e();
                do {
                    r--;
                    while (r > 1 && (r % 2)) r >>= 1;
                    if (!g(op(d[r], sm))) {
                        while (r < size) {
                            push(r);
                            r = (2 * r + 1);
                            if (g(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<S> d;
            std::vector<F> lz;

            void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); }
            void all_apply(int k, F f) {
                d[k] = mapping(f, d[k]);
                if (k < size) lz[k] = composition(f, lz[k]);
            }
            void push(int k) {
                all_apply(2 * k, lz[k]);
                all_apply(2 * k + 1, lz[k]);
                lz[k] = id();
            }
    };

}  // namespace atcoder


using namespace atcoder;

using S = long long;
using F = long long;

S op(S a, S b) { return std::max(a, b); }
S e() { return 0; }
S mapping(F f, S x) { return max(f, x); }
F composition(F f, F g) { return max(f, g); }
F id() { return 0; }

bool cmp(pair<pair<int, int>, int> a, pair<pair<int, int>, int> b)
{
    if (a.first.first == b.first.first)
    {
        return a.first.second > b.first.second;
    }
    return a.first.first < b.first.first;
}

int main(void)
{
	cin.tie(0);
	ios::sync_with_stdio(false);

	int n, a, b, c;
	vector <pair<pair<int, int>, int>> v;
    set <int> s;
	map <int, int> idx;

    cin >> n;

    for (int i = 0; i < n; i++)
    {
        cin >> a >> b >> c;
        v.push_back(make_pair(make_pair(a, b), c));
        s.insert(b);
    }

    int num = 0;
    for (auto it : s)
    {
        idx[it] = num++;
    }
    atcoder::lazy_segtree <S, op, e, F, mapping, composition, id> seg(num);
    for (int i = 0; i < n; i++)
    {
        v[i].first.second = idx[v[i].first.second];
    }
    sort(v.begin(), v.end(), cmp);
    for (int i = 0; i < n; i++)
    {
        long long int val = seg.prod(0, v[i].first.second);
        seg.apply(v[i].first.second, val + v[i].second);
    }

    cout << seg.all_prod() << '\n';
	return 0;
}