#include <bits/stdc++.h>
using namespace std;
int main() {
  long n, m, k, a[100000], b[100000], c[100000], i, j, l, zapr;
  long long answ = 0;
  cin >> n >> m >> k;
  for (i = 0; i < m; i++) {
    cin >> a[i] >> b[i] >> c[i];
  }
  for (i = 0; i < k; i++) {
    cin >> zapr;
    for (j = 0; j < m; j++) {
      if (zapr >= a[j] && zapr <= b[j]) {
        answ += (zapr - a[j]) + c[j];
      }
    }
  }
  cout << answ;
  return 0;
}
