/* -*- coding: utf-8 -*-
 *
 * 2408.cc:  No.2408 Lakes and Fish - yukicoder
 */

#include<cstdio>
#include<algorithm>
 
using namespace std;

/* constant */

const int MAX_N = 100000;
const int MAX_M = 100000;
const int INF = 1 << 30;

/* typedef */

typedef long long ll;

/* global variables */

int ls[MAX_N];

/* subroutines */

/* main */

int main() {
  int n, m;
  scanf("%d%d", &n, &m);
  for (int i = 0; i < n; i++) scanf("%d", ls + i);

  ll sum = 0;
  while (m--) {
    int f, b, w;
    scanf("%d%d%d", &f, &b, &w);

    int k = lower_bound(ls, ls + n, f) - ls;
    int c0 = (k > 0) ? f - ls[k - 1] : INF;
    int c1 = (k < n) ? ls[k] - f : INF;
    int c = min(c0, c1);
    sum += max(b, w - c);
  }

  printf("%lld\n", sum);

  return 0;
}