import sys
sys.setrecursionlimit(5*10**5)
input = sys.stdin.readline
from collections import defaultdict, deque, Counter
from heapq import heappop, heappush
from bisect import bisect_left, bisect_right
from math import gcd

n,m = map(int,input().split())
l = [-10**18] + list(map(int,input().split())) + [10**18]
ans = 0
for i in range(m):
    f,bi,wi = map(int,input().split())
    t = bisect_right(l, f)
    d = min(l[t]-f, f-l[t-1])
    ans += max(bi, wi-d)

print(ans)