#include <iostream>
#include <vector>
#include <algorithm>

int absz( const int x )
{
    return x > 0 ? x : -x;
}

int main( void )
{
    int N = 1, M = 1;
    std::cin >> N >> M;
    std::vector<int> L( N );
    for (int i = 0;i < N;i++) {
        std::cin >> L[i];
    }
    int F = 0, B = 0, W = 0;
    int sum = 0;
    for (int i = 0; i < M; i++) {
        std::cin >> F >> B >> W;        
        auto l = std::lower_bound( L.begin(), L.end(), F );
        auto l2 = l;
        if (l == L.end()) --l;
        if (l2 != L.begin()) --l2;
        int d1 = absz( *l - F );
        int d2 = absz( *l2 - F );
        int nearest = d1 > d2 ? d2 : d1;
        if (nearest < 1) {
            sum += W;
        }
        else if (nearest < W - B) {
            sum += W - nearest;
        }
        else {
            sum += B;
        }
    }
    std::cout << sum;

    return 0;
}