#include <bits/stdc++.h>
const long long mod = (long long)1e9 + 7;
const int maxn = (int)1e5 + 1;
long long inf = 1LL << 60;
using namespace std;
inline void read(int &n) {
  int x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = 10 * x + ch - '0';
    ch = getchar();
  }
  n = x * f;
}
inline void read(long long &n) {
  long long x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = 10ll * x + ch - '0';
    ch = getchar();
  }
  n = x * f;
}
int a[20];
int rule[20][20];
long long dp[1 << 19][19];
int bitCount(int n) {
  int count = 0;
  while (n) {
    count++;
    n &= (n - 1);
  }
  return count;
}
int main() {
  setlocale(LC_ALL, "Russian");
  ios_base::sync_with_stdio(0);
  int n, m, k;
  cin >> n >> m >> k;
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i < k; i++) {
    int u, v, d;
    cin >> u >> v >> d;
    u--, v--;
    rule[u][v] = d;
  }
  for (int i = 0; i < n; i++) dp[1 << i][i] = a[i];
  for (int mask = 0; mask < 1 << n; mask++) {
    for (int i = 0; i < n; i++) {
      if (mask & (1 << i)) {
        for (int j = 0; j < n; j++) {
          if (!(mask & (1 << j))) {
            int nmask = mask | (1 << j);
            dp[nmask][j] = max(dp[nmask][j], dp[mask][i] + a[j] + rule[i][j]);
          }
        }
      }
    }
  }
  for (int mask = 0; mask < 1 << n; mask++) {
    for (int i = 0; i < n; i++) {
      if (bitCount(mask) == m) {
        ans = max(ans, dp[mask][i]);
      }
    }
  }
  cout << ans;
  return 0;
}
