n,m=map(int,input().split())
L=list(map(int,input().split()))
L=[-10**10]+L+[10**10]
ans=0
for i in range(m):
	x,a,b=map(int,input().split())
	co=0
	for j in reversed(range(60)):
		co+=2**j
		if co>=n+2:
			co-=2**j
		else:
			if L[co]>x:
				co-=2**j
	ans+=max(a,b-abs(x-L[co]),b-abs(x-L[co+1]))
print(ans)