#include <bits/stdc++.h>
using namespace std;
long long a[111111];
vector<int> neg[111111];
vector<int> pos[111111];
long long s, c, t;
int n, m, k;
int main() {
  cin >> n >> m >> k;
  for (int(i) = 0; (i) < (m); ++(i)) {
    int first, second, z;
    cin >> first >> second >> z;
    --first;
    --second;
    pos[first].push_back(z);
    neg[second].push_back(z + second - first);
  }
  s = 0;
  c = 0;
  for (int(i) = 0; (i) < (n); ++(i)) {
    s += c;
    for (int(j) = 0; (j) < ((int)pos[i].size()); ++(j)) {
      c++;
      s += pos[i][j];
    }
    a[i] = s;
    for (int(j) = 0; (j) < ((int)neg[i].size()); ++(j)) {
      c--;
      s -= neg[i][j];
    }
  }
  long long ans = 0;
  for (int(i) = 0; (i) < (k); ++(i)) {
    int pos;
    cin >> pos;
    ans += a[--pos];
  }
  cout << ans << endl;
}
