#include <bits/stdc++.h>
using namespace std;
long long l[100005], r[100005], arr[100005];
int main() {
  long long i, j;
  long long n, m, k;
  while (cin >> n >> m >> k) {
    for (i = 1; i <= m; i++) cin >> l[i] >> r[i] >> arr[i];
    long long ans = 0;
    while (k--) {
      cin >> j;
      for (i = 1; i <= m; i++) {
        if (j < l[i] || j > r[i]) continue;
        ans += arr[i];
        ans += j - l[i];
      }
    }
    cout << ans << endl;
  }
  return 0;
}
