#include <bits/stdc++.h>
#define nah_id_win ios_base::sync_with_stdio(0); cin.tie(0)
#define ull unsigned long long
#define int long long
#define pb push_back
#define pob pop_back
#define pf push_front
#define pof pop_front
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
using namespace std;
const int MOD = 1e9 + 7;

void with_this_treasure_i_summon(string name){
	freopen((name + ".in").c_str(), "r", stdin); 
	freopen((name + ".out").c_str(), "w", stdout);
}

signed main(){
	nah_id_win;
	int n, m; cin >> n >> m;
	vector<int> l(n); 
	for (auto &x : l){
		cin >> x;
	}
	
	vector<pair<int, pair<int, int>>> ikan(m);
	for (auto &[f, bw] : ikan){
		int b, w; cin >> f >> b >> w;
		bw = {b, w};
	}	
	
	int ans = 0; int cost = 0;
	for (auto &[f, bw] : ikan){
		//cout << "ikan-----------------\n";
		//cout << "f " << f << "\n";
		auto it1 = upper_bound(all(l), f);
		
		
		int shortest = 1e18;
		if (it1 != l.end()){
			//cout << "kekanan " << *it1 - f << "\n";
			shortest = min(shortest, *it1 - f);
		}
		if (it1 != l.begin()){
			auto it2 = prev(it1);
			//cout << "kekiri " << f - *it2 << "\n";
			shortest = min(shortest, f - *it2);
		}
		
		//cout << "bedanya " << bw.se - bw.fi << "\n";
		
		if (shortest <= (bw.se - bw.fi)){
			//cout << "gelap\n";
			ans += bw.se;
			cost += shortest;
		}
		else{
			//cout << "terang\n";
			ans += bw.fi;
		}
	}	
	
	cout << ans - cost << "\n";
}