#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;
#define drep(i, cc, n) for (ll i = (cc); i <= (n); ++i)
#define rep(i, n) drep(i, 0, n - 1)
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define fi first
#define se second

mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
const ll MOD1000000007 = 1000000007;
const ll MOD998244353 = 998244353;
const ll MOD[3] = {999727999, 1070777777, 1000000007};
const ll LINF = 1LL << 60;
const int IINF = (1 << 30) - 1;

template<typename T> struct Edge{
    int to; T w;
    Edge(int to_, T w_=1){
        to = to_;
        w=w_;
    }
};
template<typename T> using Tree = vector<vector<Edge<T>>>;
template<typename T> using Graph = vector<vector<Edge<T>>>;
/* 容量&重み付きエッジ for Dinic */
template<typename T> struct REdge{
    int to;
    T cap;
    T cost;
    int rev;
    REdge(int to_, T cap_, T cost_=1){
        to = to_;
        cap = cap_;
        cost = cost_;
    }
    
    REdge(int to_, T cap_, T cost_, int rev_){
        to = to_;
        cap = cap_;
        cost = cost_;
        rev = rev_;
    }
};

/* 残余グラフ for Dinic */
template<typename T> using RGraph = vector<vector<REdge<T>>>;

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    
    ll n, m; cin >> n >> m;
    vector<ll> l(n); rep(i, n) cin >> l[i];
    vector<ll> f(m), b(m), w(m); rep(i, m) cin >> f[i] >> b[i] >> w[i];

    ll ans = 0;
    for(ll i=0; i<m; i++){
        auto itr = lower_bound(all(l), f[i]);
        ll sa = b[i];
        if(itr!=l.end()){
            sa = max(sa, w[i]-abs(f[i]-*itr));
        }
        if(itr!=l.begin()){
            itr--;
            sa = max(sa, w[i]-abs(f[i]-*itr));
        }

        ans += sa;
    }
    cout << ans << endl;
}