#include <bits/stdc++.h>
#define ll long long
using namespace std;
int n, m;
const ll inf = 1e16 + 5;
const int nmax = 3e5 + 2;
#define left deobiceicineintreabasussy
#define right deobiceicineintreababaka
struct AINT {
ll tree[4 * nmax];
ll query(int l, int r, int node = 1, int cl = 1, int cr = n) {
//cout << l << ' ' << r << '\t' << cl << ' ' << cr << ' ' << tree[node] << '\n';
if(r < cl || cr < l)
return inf;
if(l <= cl && cr <= r)
return tree[node];
int mid = cl + cr >> 1;
return min(query(l, r, 2 * node, cl, mid), query(l, r, 2 * node + 1, mid + 1, cr));
}
void upd(int poz, ll val, int node = 1, int cl = 1, int cr = n) {
tree[node] = min(tree[node], val);
if(cl == cr)
return;
int mid = cl + cr >> 1;
if(poz <= mid)
return upd(poz, val, 2 * node, cl, mid);
return upd(poz, val, 2 * node + 1, mid + 1, cr);
} // asta se numeste smenul lui nicu
void construct(int node = 1, int cl = 1, int cr = n) {
tree[node] = inf;
if(cl == cr)
return;
int mid = cl + cr >> 1;
construct(2 * node, cl, mid);
construct(2 * node + 1, mid + 1, cr);
}
};
AINT left, right;
#define norm deobiceicineintreaba
map<int,int> norm;
int main() {
cin >> m >> n;
vector<tuple<int,int,int,int> > v(m);
for(auto &[a, b, c, d] : v) {
cin >> a >> b >> c >> d;
norm[a];
norm[b];
norm[c];
}
norm[1];
norm[n];
int cnt = 1;
for(auto &x : norm)
x.second = cnt++;
n = cnt - 1;
left.construct();
right.construct();
left.upd(1, 0);
right.upd(n, 0);
ll minn = inf;
for(auto [a, b, c, d] : v) {
a = norm[a];
b = norm[b];
c = norm[c];
ll l = left.query(a, c), r = right.query(c, b);
//cout << l << ' ' << r << '\n';
minn = min(minn, l + r + d);
left.upd(c, l + d);
right.upd(c, r + d);
}
if(minn >= 1e16 + 1)
cout << -1 << '\n';
else
cout << minn << '\n';
}
