#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:16777216")
using namespace std;
template <class T>
void pv(T a, T b) {
  for (T i = a; i != b; ++i) cout << *i << " ";
  cout << endl;
}
int n, m, k, q;
int a[1 << 20], b[1 << 20], c[1 << 20];
long long count(int l, int r, int x, int pos) {
  if (pos < l || pos > r) return 0;
  return (pos - l) + x;
}
int main() {
  cin >> n >> m >> k;
  for (int i = 0; i < m; i++) {
    cin >> a[i] >> b[i] >> c[i];
  }
  long long tot = 0;
  while (k--) {
    cin >> q;
    for (int i = 0; i < m; i++) {
      tot += count(a[i], b[i], c[i], q);
    }
  }
  cout << tot << endl;
  return 0;
}
