#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, i, j, k, m, l;
  int a[100001], b[100001], c[100001];
  long long total;
  while (scanf("%d%d%d", &n, &m, &k) != EOF) {
    total = 0;
    for (i = 1; i <= m; i++) scanf("%d%d%d", a + i, b + i, c + i);
    for (l = 1; l <= k; l++) {
      scanf("%d", &j);
      for (i = 1; i <= m; i++)
        if (j >= a[i] && j <= b[i]) total = total + c[i] + j - a[i];
    }
    cout << total << endl;
  }
}
