#include<stdio.h>
long long int l[100005];
int main()
{
	long long int n, m;
	scanf("%lld %lld", &n, &m);
	long long int i;
	for (i = 0; i < n; i++)
		scanf("%lld", &l[i + 1]);
	l[n + 1] = 1e18;
	l[0] = -1e18;
	long long int ans = 0;
	long long int f, b, w, dist;
	long long int min, mid, max;
	for (i = 0; i < m; i++)
	{
		scanf("%lld %lld %lld", &f, &b, &w);
		min = -1;
		max = n + 1;
		while (max - min > 1)
		{
			mid = (max + min) / 2;
			if (l[mid] > f)
				max = mid;
			else
				min = mid;
		}
		dist = f - l[min];
		if (dist > l[max] - f)
			dist = l[max] - f;
		if (b > w - dist)
			ans += b;
		else
			ans += w - dist;
	}
	printf("%lld\n", ans);
	return 0;
}