#include <bits/stdc++.h>
using namespace std;
inline void read(register int *n) {
  register char c;
  *n = 0;
  do {
    c = getchar();
  } while (c < '0' || c > '9');
  do {
    *n = c - '0' + *n * 10;
    c = getchar();
  } while (c >= '0' && c <= '9');
}
int n, m, k;
pair<pair<int, int>, int> Q[101000];
int main() {
  cin >> n >> m >> k;
  for (register int i = (0); i < (int)(m); ++i)
    cin >> Q[i].first.first >> Q[i].first.second >> Q[i].second;
  long long sum = 0;
  for (register int i = (0); i < (int)(k); ++i) {
    int x;
    cin >> x;
    for (register int i = (0); i < (int)(m); ++i)
      if (Q[i].first.first <= x && x <= Q[i].first.second)
        sum += x - Q[i].first.first + Q[i].second;
  }
  cout << sum << "\n";
  return 0;
}
