#include <bits/stdc++.h>
using namespace std;
#define int long long
int a[1005],b[1005],c[1005],d[1005];
int dp[1005][1005];
int currl[1005];
int currr[1005];
const int inf = 1e18;
signed main() {
for (int i = 0; i <= 1000; i++) {
for (int j = 0; j <= 1000; j++) dp[i][j]=inf;
}
int m, n; cin >> m >> n;
for (int i = 0; i < m; i++) {
cin >> a[i] >> b[i] >> c[i] >> d[i];
}
for (int i = m-1; i >= 0; i--) {
dp[i][i]=d[i];
// find the continuous to left for each thing
// and smallest continuous to right
// then use curr to merge them
//cout << i << "\n";
for (int j = 0; j < m; j++) {
for (int k = 0; k < m; k++) {
if (a[j] <= b[k] && a[j] <= a[i] && a[i] <= b[k] && b[k] <= b[i]) { // checking if they overlap correctly
// checking if c[i] puts it in the thing
if (a[j] <= c[i] && c[i] <= b[k]) dp[j][i] = min(dp[j][i], dp[j][k]+d[i]);
}
if (a[j] <= b[k] && a[i] <= a[j] && a[j] <= b[i] && b[i] <= b[k]) {
if (a[j] <= c[i] && c[i] <= b[k]) dp[i][k] = min(dp[i][k], dp[j][k]+d[i]);
}
}
}
/*for (int j = 0; j < m; j++) {
for (int k = 0; k < m; k++) {
cout << dp[j][k] << " ";
}
cout << "\n";
}
cout << "\n";*/
//cout << dp[i][i] << "\n";
}
int minnum = inf;
for (int i = 0; i < m; i++) {
for (int j = 0; j < m; j++) {
if (a[i]==1 && b[j]==n) minnum=min(minnum, dp[i][j]);
}
}
if (minnum==inf) cout << -1 << "\n";
else cout << minnum << "\n";
return 0;
}
