#include <bits/stdc++.h>
using namespace std;
#define ll long long
const ll inf = 1e18;
int main() {
int m, n; cin >> m >> n;
int L[m], R[m], T[m], C[m];
for (int i = 0; i < m; i++) cin >> L[i] >> R[i] >> T[i] >> C[i];
ll dpLeft[m], dpRight[m];
for (int i = 0; i < m; i++) {
dpLeft[i] = dpRight[i] = inf;
if (L[i] == 1) dpLeft[i] = C[i];
if (R[i] == n) dpRight[i] = C[i];
for (int j = 0; j < i; j++) {
if (L[i] <= T[j] && T[j] <= R[i]) {
dpLeft[i] = min(dpLeft[i], dpLeft[j] + C[i]);
dpRight[i] = min(dpRight[i], dpRight[j] + C[i]);
}
}
}
ll opt = inf;
for (int i = 0; i < m; i++) {
opt = min(opt, dpLeft[i] + dpRight[i] - C[i]);
}
if (opt == inf) cout << -1 << endl;
else cout << opt << endl;
return 0;
}
