#include <bits/stdc++.h>
#define int long long
using namespace std;
map<int,int> dpr; // r at
map<int,int> dpc; // c at
// increase(strict)
void insertr(int r,int cost){
if (dpr.lower_bound(r)!=dpr.end()&&dpr.lower_bound(r)->second<=cost) return;
dpr[r]=cost;
auto it=dpr.find(r);
while (it!=dpr.begin()){
if (prev(it)->second>=cost) dpr.erase(prev(it));
else break;
}
}
void insertc(int c,int cost){
if (dpc.lower_bound(c)!=dpc.end()&&dpc.lower_bound(c)->second<=cost) return;
dpc[c]=cost;
auto it=dpc.find(c);
while (it!=dpc.begin()){
if (prev(it)->second>=cost) dpc.erase(prev(it));
else break;
}
}
struct device{
int l,r,c,d;
bool operator<(const device &o)const{return l<o.l;}
};
signed main(){
int n,m;
cin>>n>>m;
vector<device> v(n);
for (auto &[l,r,c,d]:v) cin>>l>>r>>c>>d;
int i=0,ans=1e18;
for (int i=0;i<n;i++){
map<pair<int,int>,int> dp; // l,r,cost
dp[{v[i].l,v[i].r}]=v[i].d;
for (int j=i-1;j>=0;j--){
vector<array<int,3>> ok;
for (auto k:dp){
if (v[j].c>k.first.second||v[j].c<k.first.first) continue;
ok.push_back({k.first.first,k.first.second,k.second});
}
for (auto [l,r,cost]:ok){
dp.insert({{min(v[j].l,l),max(v[j].r,r)},v[j].d+cost});
dp[{min(v[j].l,l),max(v[j].r,r)}]=min(dp[{min(v[j].l,l),max(v[j].r,r)}],v[j].d+cost);
}
}
if (dp.count({1,m})) ans=min(ans,dp[{1,m}]);
// cerr<<ans<<endl;
}
if (ans!=1e18) cout<<ans;
else cout<<-1;
}
