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