#include <bits/stdc++.h> 
using namespace std;
using ll =long long;
#define all(v) v.begin(),v.end()
 #define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)

ll INF=2e18;


int main() {
    ios::sync_with_stdio(false);
  cin.tie(0);

ll N,M;cin>>N>>M;
vector<ll> L(N);
for(ll i=0;i<N;i++) cin>>L[i];

vector<ll> F(M),B(M),W(M);
for(ll i=0;i<M;i++) cin>>F[i]>>B[i]>>W[i];

ll ans=0;
for(ll i=0;i<M;i++) {
  ll ind=lower_bound(all(L),F[i])-L.begin();
  ll ma=-INF;
  if(ind>0) {
    ma=max(ma,max(B[i],W[i]-(F[i]-L[ind-1])));
  }
  if(ind<L.size()) {
    ma=max(ma,max(B[i],W[i]-(L[ind]-F[i])));
  }
  ans+=ma;
}

cout<<ans<<endl;
}