#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef unsigned long long ull;
typedef long double ld;
int dx[8] = { 1, 0, -1, 0, 1, 1, -1, -1 }, dy[8] = { 0, 1, 0, -1, 1, -1, 1, -1 };
const long long mod = 998244353;
const ll inf = 1LL << 60;
const int INF = 5e8;

int main()
{
    int n, m;
    cin >> n >> m;
    vector<int> l(n);
    for (int i = 0; i < n; i++)
        cin >> l[i];

    ll ans = 0;
    for (int i = 0; i < m; i++) {
        int f, b, w;
        cin >> f >> b >> w;
        auto it = lower_bound(l.begin(), l.end(), f);
        if (it == l.begin()) {
            ans += max(b, -(l[0] - f) + w);
        } else if (it == l.end()) {
            ans += max(b, -(f - l[n - 1]) + w);
        } else {
            ans += max({ b, -(*it - f) + w, -(f - *prev(it)) + w });
        }
    }
    cout << ans << endl;
}