#include <bits/stdc++.h>
using namespace std;
struct ladder {
  int a;
  int b;
  int c;
};
int main() {
  int i, j, n, m, k, s;
  long long int SUM = 0;
  ladder l;
  vector<int> solve;
  vector<ladder> v;
  cin >> n >> m >> k;
  for (i = 0; i < m; i++) {
    cin >> l.a >> l.b >> l.c;
    v.push_back(l);
  }
  for (i = 0; i < k; i++) {
    cin >> s;
    solve.push_back(s);
  }
  vector<long long int> sum(k);
  for (i = 0; i < m; i++)
    for (j = 0; j < k; j++)
      if (solve[j] >= v[i].a && solve[j] <= v[i].b)
        sum[j] += 1ll * (v[i].c + solve[j] - v[i].a);
  for (i = 0; i < k; i++) SUM += 1ll * sum[i];
  cout << SUM;
  return 0;
}
