#include <bits/stdc++.h>
using namespace std;
int n, m, k;
int a[10000000], b[10000000], c[10000000];
int q[105];
long long sum(long long x) { return x * (x + 1) / 2; }
int main() {
  long long ans = 0;
  cin >> n >> m >> k;
  for (int i = 0; i < (m); i++) cin >> a[i] >> b[i] >> c[i];
  for (int i = 0; i < (k); i++) cin >> q[i];
  for (int i = 0; i < (m); i++) {
    for (int j = 0; j < (k); j++) {
      if (q[j] >= a[i] && q[j] <= b[i]) {
        ans += q[j] - a[i] + c[i];
      }
    }
  }
  cout << ans << "\n";
}
