#include <bits/stdc++.h>
struct node {
  int x, y, z;
} a[100010];
int main() {
  int n, m, k;
  while (~scanf("%d%d%d", &n, &m, &k)) {
    for (int i = 1; i <= m; i++) scanf("%d%d%d", &a[i].x, &a[i].y, &a[i].z);
    int x;
    long long sum = 0;
    for (int i = 1; i <= k; i++) {
      scanf("%d", &x);
      for (int j = 1; j <= m; j++) {
        if (x >= a[j].x && x <= a[j].y) sum += x + a[j].z - a[j].x;
      }
    }
    printf("%lld\n", sum);
  }
  return 0;
}
