#include <bits/stdc++.h>
using namespace std;
int n, m, k, a[100009], b[100009], c[100009];
int kl[128];
int main() {
  int i, j;
  cin >> n >> m >> k;
  for (i = 0; i < m; ++i) cin >> a[i] >> b[i] >> c[i];
  for (i = 0; i < k; ++i) cin >> kl[i];
  unsigned long long s = 0;
  for (i = 0; i < m; ++i)
    for (j = 0; j < k; ++j) {
      if (kl[j] >= a[i] && kl[j] <= b[i]) s += (kl[j] - a[i] + c[i]);
    }
  cout << s << '\n';
  return 0;
}
