#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define endl "\n"

const int N = 1e5 + 5;

int n, m;

ll koor[N];

int binserbig ( int y ){
    int l = 1, r = n, rec = -1;
    while ( l <= r ){
        int mid = ( l + r ) / 2;
        if ( koor[mid] <= y ){
            l = mid + 1;
            rec = mid;
        }
        else r = mid - 1;
    }
    return rec;
}

int binsersmall ( int y ){
    int l = 1, r = n, rec = -1;
    while ( l <= r ){
        int mid = ( l + r) / 2;
        if ( koor[mid] >= y ){
            r = mid - 1;
            rec = mid;
        }
        else l = mid + 1;
    }
    return rec;
}

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); 

    cin >> n >> m;

    for ( int i = 1; i <= n; i++) cin >> koor[i];

    ll ans = 0;

    for ( int i = 1; i <= m; i++){
        ll k, un, nun; cin >> k >> un >> nun;

        // nun -> dibawah pohon
        
        int idxbigger = binserbig ( k );
        int idxsmaller = binsersmall ( k );

        ll temp = un;

        if ( idxbigger != -1 ){
            temp = max ( nun - abs ( koor[idxbigger] - k), temp);
        }

        if ( idxsmaller != -1 ){
            temp = max ( nun - abs ( koor[idxsmaller] - k), temp);
        }
        
        ans += temp;
    }

    cout << ans << endl;

}