//Author:xht37
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
const int N = 1e5 + 7, inf = 0x3f3f3f3f;
int n, l, r, f[N];
struct T {
    int l, r, x;
    inline bool operator < (const T w) const {
        return r < w.r || (r == w.r && l < w.l);
    }
} a[N], t[N<<2];

void build(int p, int l, int r) {
    t[p].l = l;
    t[p].r = r;
    if (l == r) {
        t[p].x = f[l];
        return;
    }
    int mid = (l + r) >> 1;
    build(p << 1, l, mid);
    build(p << 1 | 1, mid + 1, r);
    t[p].x = min(t[p<<1].x, t[p<<1|1].x);
}

void change(int p, int x, int y) {
    if (t[p].l == t[p].r) {
        t[p].x = y;
        return;
    }
    int mid = (t[p].l + t[p].r) >> 1;
    if (x <= mid) change(p << 1, x, y);
    else change(p << 1 | 1, x, y);
    t[p].x = min(t[p<<1].x, t[p<<1|1].x);
}

int ask(int p, int l, int r) {
    if (l <= t[p].l && r >= t[p].r) return t[p].x;
    int mid = (t[p].l + t[p].r) / 2, ans = inf;
    if (l <= mid) ans = min(ans, ask(p << 1, l, r));
    if (r > mid) ans = min(ans, ask(p << 1 | 1, l, r));
    return ans;
}

int main() {
    cin >> n >> l >> r;
    for (int i = 1; i <= n; i++)
        scanf("%d %d %d", &a[i].l, &a[i].r, &a[i].x), a[i].l = max(l, a[i].l), a[i].r = min(r, a[i].r);
    sort(a + 1, a + n + 1);
    memset(f, 0x3f, sizeof(f));
    f[l-1] = 0;
    build(1, l - 1, r);
    for (int i = 1; i <= n; i++) {
        if (a[i].l > a[i].r) continue;
        f[a[i].r] = min(f[a[i].r], ask(1, a[i].l - 1, a[i].r) + a[i].x);
        change(1, a[i].r, f[a[i].r]);
    }
    if (f[r] == inf) puts("-1");
    else cout << f[r] << endl;
    return 0;
}

//Author:xht37
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
const int N = 1e5 + 7, inf = 0x3f3f3f3f;
int n, l, r, f[N];
struct T {
	int l, r, x;
	inline bool operator < (const T w) const {
		return r < w.r || (r == w.r && l < w.l);
	}
} a[N], t[N<<2];

void build(int p, int l, int r) {
	t[p].l = l;
	t[p].r = r;
	if (l == r) {
		t[p].x = f[l];
		return;
	}
	int mid = (l + r) >> 1;
	build(p << 1, l, mid);
	build(p << 1 | 1, mid + 1, r);
	t[p].x = min(t[p<<1].x, t[p<<1|1].x);
}

void change(int p, int x, int y) {
	if (t[p].l == t[p].r) {
		t[p].x = y;
		return;
	}
	int mid = (t[p].l + t[p].r) >> 1;
	if (x <= mid) change(p << 1, x, y);
	else change(p << 1 | 1, x, y);
	t[p].x = min(t[p<<1].x, t[p<<1|1].x);
}

int ask(int p, int l, int r) {
	if (l <= t[p].l && r >= t[p].r) return t[p].x;
	int mid = (t[p].l + t[p].r) / 2, ans = inf;
	if (l <= mid) ans = min(ans, ask(p << 1, l, r));
	if (r > mid) ans = min(ans, ask(p << 1 | 1, l, r));
	return ans;
}

int main() {
	cin >> n >> l >> r;
	for (int i = 1; i <= n; i++)
		scanf("%d %d %d", &a[i].l, &a[i].r, &a[i].x), a[i].l = max(l, a[i].l), a[i].r = min(r, a[i].r);
	sort(a + 1, a + n + 1);
	memset(f, 0x3f, sizeof(f));
	f[l-1] = 0;
	build(1, l - 1, r);
	for (int i = 1; i <= n; i++) {
		if (a[i].l > a[i].r) continue;
		f[a[i].r] = min(f[a[i].r], ask(1, a[i].l - 1, a[i].r) + a[i].x);
		change(1, a[i].r, f[a[i].r]);
	}
	if (f[r] == inf) puts("-1");
	else cout << f[r] << endl;
	return 0;
}