import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Scanner;

class Main {

	void run() {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		PrintWriter pw = new PrintWriter(System.out);
		int[][] v = new int[N][3];
		for (int i = 0; i < N; ++i) {
			v[i][0] = sc.nextInt();
			v[i][1] = sc.nextInt();
			v[i][2] = sc.nextInt();
			--v[i][0];
			--v[i][1];
		}
		compress(v);
		Arrays.sort(v, new Comparator<int[]>() {
			@Override
			public int compare(int[] o1, int[] o2) {
				if (o1[0] != o2[0]) {
					return Integer.compare(o1[0], o2[0]);
				} else {
					return -Integer.compare(o1[1], o2[1]);
				}
			}
		});

		SegmentTree seg = new SegmentTree(N + 1);
		for (int i = 0; i < N; ++i) {
			long val = seg.query(0, v[i][1]);
			seg.update(v[i][1], val + v[i][2]);
		}
		pw.println(seg.query(0, N + 1));
		pw.close();
	}

	void compress(int[][] a) {
		int n = a.length;
		int[][] tmp = new int[n][4];
		for (int i = 0; i < n; ++i) {
			for (int j = 0; j < a[i].length; ++j) {
				tmp[i][j] = a[i][j];
			}
			tmp[i][3] = i;
		}
		Arrays.sort(tmp, new Comparator<int[]>() {
			@Override
			public int compare(int[] o1, int[] o2) {
				return Integer.compare(o1[0], o2[0]);
			}
		});

		int p = 0;
		for (int i = 0; i < n; ++i) {
			if (i + 1 < n && tmp[i][0] != tmp[i + 1][0]) {
				tmp[i][0] = p++;
			} else {
				tmp[i][0] = p;
			}
		}
		Arrays.sort(tmp, new Comparator<int[]>() {
			@Override
			public int compare(int[] o1, int[] o2) {
				return Integer.compare(o1[1], o2[1]);
			}
		});
		p = 0;
		for (int i = 0; i < n; ++i) {
			if (i + 1 < n && tmp[i][1] != tmp[i + 1][1]) {
				tmp[i][1] = p++;
			} else {
				tmp[i][1] = p;
			}
		}
		for (int i = 0; i < n; ++i) {
			for (int j = 0; j < 3; ++j) {
				a[tmp[i][3]][j] = tmp[i][j];
			}
		}
	}

	class SegmentTree {
		int n;
		long[] v;

		public SegmentTree(int n_) {
			n = 1;
			while (n < n_) {
				n *= 2;
			}
			v = new long[2 * n - 1];
		}

		void update(int k, long val) {
			k += n - 1;
			v[k] = Math.max(v[k], val);
			while (k > 0) {
				k = (k - 1) / 2;
				v[k] = Math.max(v[2 * k + 1], v[2 * k + 2]);
			}
		}

		long query(int a, int b) {
			return query(0, n, a, b, 0);
		}

		long query(int l, int r, int a, int b, int k) {
			if (r <= a || b <= l)
				return 0;
			else if (a <= l && r <= b)
				return v[k];
			else {
				return Math.max(query(l, (l + r) / 2, a, b, 2 * k + 1), query((l + r) / 2, r, a, b, 2 * k + 2));
			}
		}
	}

	void tr(Object... objects) {
		System.out.println(Arrays.deepToString(objects));
	}

	public static void main(String[] args) throws FileNotFoundException {
		new Main().run();
	}
}