#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, k, t;
  cin >> n >> m >> k;
  int a[100000] = {};
  int b[100000] = {};
  int c[100000] = {};
  long long sum = 0;
  for (int i = 0; i < m; i++) cin >> a[i] >> b[i] >> c[i];
  for (int i = 0; i < k; i++) {
    cin >> t;
    for (int j = 0; j < m; j++)
      if (a[j] <= t && t <= b[j]) sum += c[j] + t - a[j];
  }
  cout << sum << endl;
  return 0;
}
