#include <bits/stdc++.h>
using namespace std;
const int MAXN = 100100;
int a[MAXN], b[MAXN], c[MAXN], d[MAXN];
int main() {
  int n, m, q;
  long long ans = 0;
  scanf("%d%d%d", &n, &m, &q);
  for (int i = 0; i < m; ++i) {
    scanf("%d%d%d", &a[i], &b[i], &c[i]);
  }
  for (int i = 0; i < q; ++i) {
    scanf("%d", &d[i]);
    for (int j = 0; j < m; ++j) {
      if (a[j] <= d[i] && d[i] <= b[j]) {
        ans += c[j] + (d[i] - a[j]);
      }
    }
  }
  printf("%I64d\n", ans);
  return 0;
}
