#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, k;
  cin >> n >> m >> k;
  int a[m];
  int b[m];
  int a0[m];
  for (int i = 0; i < m; i++) cin >> a[i] >> b[i] >> a0[i];
  long long sum = 0;
  int c;
  for (int i = 0; i < k; i++) {
    cin >> c;
    for (int j = 0; j < m; j++) {
      if (c < a[j] || c > b[j]) continue;
      int x = c - a[j];
      sum += a0[j] + x;
    }
  }
  cout << sum << "\n";
}
