#include <bits/stdc++.h>
using namespace std;
const int MAXM = 1 << 17;
int lo[MAXM], hi[MAXM], sh[MAXM];
int n, m, k;
int main() {
  scanf("%d %d %d", &n, &m, &k);
  for (int i = 0; i < (int)(m); ++i) scanf("%d %d %d", &lo[i], &hi[i], &sh[i]);
  long long ans = 0;
  for (int i = 0; i < (int)(k); ++i) {
    int x;
    scanf("%d", &x);
    for (int j = 0; j < (int)(m); ++j) {
      if (lo[j] <= x && x <= hi[j]) ans += x - lo[j] + sh[j];
    }
  }
  cout << ans << endl;
  return 0;
}
