#include <algorithm>
#include <iostream>
#include <iomanip>
#include <cstring>
#include <climits>
#include <vector>
#include <cmath>
#include <set>
#define ll long long
using namespace std;

int main() {
    ll n, m;
    cin >> n >> m; 

    vector<int> pohon(n);
    for (int i = 0; i < n; i++) cin >> pohon[i];

    ll score = 0;
    for (int i = 0; i < m; i++)
    {
        ll f, b, w;
        cin >> f >> b >> w;

        ll ansdist = 1e9 + 7;
        ll l = 0, r = n-1;
        while (l <= r)
        {
            int mid = l + (r - l) / 2;

            ll dist = pohon[mid] - f;

            if (abs(dist) <= ansdist)
                ansdist = abs(dist);
            
            if (dist == 0)
            {
                ansdist = 0;
                break;
            } else if (dist < 0)
            {
                l = mid + 1;
            } else if (dist > 0)
            {
                r = mid - 1;
            }
        }

        ll profit = w - b;
        if (profit > ansdist)
        {
            score += (w - ansdist);
        } else score += b;
    }
    
    cout << score << endl;
    return 0;
}