#include <bits/stdc++.h>
using namespace std;
const int N = 100000;
int a[N], b[N], c[N];
inline long long getans(const int &i, const int &x) {
  if (a[i] > x || b[i] < x) return 0;
  return x - a[i] + c[i];
}
int main() {
  int n, m, k;
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 0; i < (int)m; i++) scanf("%d%d%d", &a[i], &b[i], &c[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++) ans += getans(j, x);
  }
  cout << ans << endl;
  return 0;
}
