#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<ll,ll>;
#define fix(x) fixed << setprecision(x)
#define asc(x) x, vector<x>, greater<x>
#define rep(i, n) for(ll i = 0; i < n; i++)
#define all(x) (x).begin(),(x).end()
template<class T>bool chmin(T&a, const T&b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool chmax(T&a, const T&b){if(a<b){a=b;return 1;}return 0;}
constexpr ll INFLL = (1LL << 62), MOD = 998244353;
constexpr int INF = (1 << 30);

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n,m;
    cin >> n >> m;
    vector<ll> l(n+2);
    l[0] = -INFLL, l[n+1] = INFLL;
    rep(i,n) cin >> l[i+1];
    ll ans = 0;
    rep(i,m){
        ll f,b,w;
        cin >> f >> b >> w;
        int x = lower_bound(all(l),f) - l.begin();
        ans += max(b, w-min(abs(f-l[x]), abs(f-l[x-1])));
    }
    cout << ans << '\n';
    return 0;
}