#include <bits/stdc++.h> #define int long long using namespace std; signed main(){ int m, n; cin>> m >> n; int fall[n+1]; pair<pair<int, int>, pair<int, int>> arr[m]; for(int i = 0; i < m;i ++) { cin >> arr[i].first.first >> arr[i].first.second >> arr[i].second.first >> arr[i].second.second; } queue<vector<bool>> q; q.push({}); for(int i = 0; i< m; i++) { int sz = q.size(); for(int j = 0; j < sz; j++) { vector<bool> a = q.front(); q.pop(); a.push_back(true); q.push(a); a.pop_back(); a.push_back(false); q.push(a); } } int minval = LONG_LONG_MAX; while(!q.empty()) { for(int i = 1; i <= n; i++) fall[i] = i; vector<bool> vec = q.front(); q.pop(); int total = 0; for(int i = 0; i < m; i++) { if(vec[i]) { total += arr[i].second.second; for(int j = 1; j <= n; j++) { if(fall[j] >= arr[i].first.first && fall[j] <= arr[i].first.second) { fall[j] = arr[i].second.first; } } } } set<int> s; for(int i = 1; i <= n; i++) { s.insert(fall[i]); } if(s.size() == 1) { minval = min(minval, total); } } cout<<minval<<'\n'; return 0; }