#include <bits/stdc++.h>
using namespace std;
const int mx = 1e5 + 777;
int main() {
  cin.tie(0);
  cout.tie(0);
  ios_base::sync_with_stdio(0);
  int n, m, k;
  cin >> n >> m >> k;
  map<int, long long> ct, add, ret;
  for (int i = 0; i < m; i++) {
    int a, b, c;
    cin >> a >> b >> c;
    ct[a]++;
    ct[b + 1]--;
    add[a] += c - 1;
    add[b + 1] -= c + b - a;
  }
  for (int i = 1; i <= mx; i++) ct[i] += ct[i - 1];
  long long cur = 0, ans = 0, x;
  for (int i = 1; i <= mx; i++) cur += add[i] + ct[i], ret[i] = cur;
  while (k--) cin >> x, ans += ret[x];
  cout << ans << "\n";
  return 0;
}
