#include <bits/stdc++.h>
using namespace std;
template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl
using ll = long long;
const int maxm = 1e5 + 10;
const int maxn = 1e6 + 10;
const ll inf = 1e18;
template<typename T> struct segtree {
T merge(T x, T y) {
return min(x, y);
}
int n;
vector<T> t;
void init(int n) {
n += 10;
this->n = n;
t.assign(n*4, inf);
}
void upd(int v, int tl, int tr, int i, T dx) {
if (tl == tr) {
t[v] = merge(t[v], dx);
} else {
int tm = (tl+tr)/2;
if (i<=tm) {
upd(2*v,tl,tm,i,dx);
} else {
upd(2*v+1,tm+1,tr,i,dx);
}
t[v] = merge(t[2*v], t[2*v+1]);
}
}
T qry(int v, int tl, int tr, int l, int r) {
if (l>tr || r<tl) {
return inf;
}
if (l <= tl && tr <= r) {
return t[v];
}
int tm = (tl+tr)/2;
return merge(qry(2*v,tl,tm,l,r), qry(2*v+1,tm+1,tr,l,r));
}
};
int m, n;
int a[maxm], b[maxm], c[maxm], d[maxm];
segtree<ll> dpL, dpR;
int main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin>>m>>n;
vector<int> ord;
ord.push_back(0);
ord.push_back(1);
ord.push_back(n);
for (int i=1; i<=m; i++) {
cin>>a[i]>>b[i]>>c[i]>>d[i];
ord.push_back(a[i]);
ord.push_back(b[i]);
ord.push_back(c[i]);
}
sort(ord.begin(),ord.end());
ord.erase(unique(ord.begin(),ord.end()),ord.end());
for (int i=1; i<=m; i++) {
a[i] = std::lower_bound(ord.begin(),ord.end(),a[i])-ord.begin();
b[i] = std::lower_bound(ord.begin(),ord.end(),b[i])-ord.begin();
c[i] = std::lower_bound(ord.begin(),ord.end(),c[i])-ord.begin();
}
int N = (int)ord.size() - 1;
dpL.init(N);
dpR.init(N);
ll ans = inf;
for (int i=1; i<=m; i++) {
int l = a[i];
int r = b[i];
ll left = (l==1 ? 0: dpL.qry(1,1,N,l,r)) + d[i];
ll right = (r==N ? 0: dpR.qry(1,1,N,l,r)) + d[i];
//cout<<left<<" "<<right<<endl;
dpL.upd(1,1,N,c[i],left);
dpR.upd(1,1,N,c[i],right);
ans = min(ans, left+right-d[i]);
}
if (ans > inf/2) ans = -1;
cout<<ans<<endl;
return 0;
}
