#include <bits/stdc++.h>
using std::cin;
using std::cout;
const int MAXX = 100005;
int starts[MAXX];
int ends[MAXX];
long long int vals[MAXX];
int main() {
  int n, m, k;
  long long int result = 0;
  cin >> n >> m >> k;
  int point;
  for (int i = 0; i < m; ++i) {
    cin >> starts[i] >> ends[i] >> vals[i];
  }
  for (int i = 0; i < k; ++i) {
    cin >> point;
    for (int j = 0; j < m; ++j) {
      if (point >= starts[j] && point <= ends[j])
        result += point - starts[j] + vals[j];
    }
  }
  cout << result;
  return 0;
}
