#include <bits/stdc++.h>
using namespace std;
int n, m, k;
const int mxn = (int)1e5 + 7;
int lo[mxn], hi[mxn], x[mxn];
int main() {
  scanf("%d", &n);
  scanf("%d", &m);
  scanf("%d", &k);
  for (int i = 0; i < m; i++) {
    scanf("%d", &lo[i]);
    scanf("%d", &hi[i]);
    scanf("%d", &x[i]);
  }
  long long ans = 0;
  for (int i = 0; i < k; i++) {
    int p;
    scanf("%d", &p);
    for (int i = 0; i < m; i++)
      if (lo[i] <= p && p <= hi[i]) {
        int offset = p - lo[i];
        ans += offset + x[i];
      }
  }
  cout << ans << endl;
  return 0;
}
