#include<bits/stdc++.h>

using namespace std;

typedef pair<int,int> nd;

typedef long long ll;

#define fi first

#define se second

int n,m,a[];

int g[][];

const int maxs = <<;

ll d[maxs][];

bool vis[maxs][];

inline int bitcount(int s)

{

    int ct = ;

    while(s){

        ct += s&;

        s >>= ;

    }

    return ct;

}

ll spfa()

{

    queue<nd>q;

    ll ans = ;

    for(int i = ; i < n; i++){

        q.push(nd(<<i,i));

        d[<<i][i] = a[i];

        vis[<<i][i] = true;

    }

    while(q.size()){

        nd &u = q.front(); vis[u.fi][u.se] = false;

        int bc = bitcount(u.fi);

        if(bc == m) { ans = max(ans,d[u.fi][u.se]); q.pop(); continue; }

        for(int i = ; i < n; i++){

            if(&(u.fi>>i)) continue;

            int ns = <<i|u.fi;

            if(d[ns][i] < d[u.fi][u.se] + g[u.se][i] + a[i]){

                d[ns][i] = d[u.fi][u.se] + g[u.se][i] + a[i];

                if(!vis[ns][i]){

                    q.push(nd(ns,i)); vis[ns][i] = true;

                }

            }

        }

        q.pop();

    }

    return ans;

}

int main()

{

    //freopen("in.txt","r",stdin);

    int k;scanf("%d%d%d",&n,&m,&k);

    for(int i = ; i < n; i++){

        scanf("%d",a+i);

    }

    while(k--){

        int x,y; scanf("%d%d",&x,&y);

        scanf("%d",g[x-]+y-);

    }

    printf("%I64d",spfa());

    return ;

}