#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, m, k;
  cin >> n >> m >> k;
  vector<long long int> a, b, c, p, r;
  for (int i = 0; i < m; i++) {
    int k;
    cin >> k;
    a.push_back(k);
    cin >> k;
    b.push_back(k);
    cin >> k;
    c.push_back(k);
    a[i]--;
    b[i]--;
  }
  for (int i = 0; i < k; ++i) {
    int d;
    cin >> d;
    p.push_back(d);
    r.push_back(0);
    p[i]--;
  }
  for (int i = 0; i < m; ++i) {
    for (int j = 0; j < k; ++j) {
      if (a[i] <= p[j] && p[j] <= b[i]) r[0] += p[j] - a[i] + c[i];
    }
  }
  long long int sum = 0;
  for (int i = 0; i < k; ++i) {
    sum += r[i];
  }
  cout << sum;
  return 0;
}
