#include <bits/stdc++.h>
using namespace std;
#define int long long
const int mod=998244353;
const int N=1e6+10;
int n,m,k;
int father[N];
int answer=1e18+10,tot;
int c[N];
struct node{
	int u,v,w;
}a[N];
void build(){
	for(int i=1;i<=n;i++){
		father[i]=i;
	}
}
bool cmp(node x,node y){
	return x.w<y.w;
}
int find(int i){
	if(father[i]!=i){
		father[i]=find(father[i]);
	}
	return father[i];
}
void Union(int x,int y){
	father[find(x)]=find(y);
}
bool vis[100];
void kruskal(){
	build();
	sort(a+1,a+m+1,cmp);
	for(int i=1;i<=m;i++){
		int x=a[i].u;
		int y=a[i].v;
		x=find(x);
		y=find(y);
		if(x!=y){
			tot++;
			Union(x,y);
			a[tot]=a[i];
		}
		if(tot==n-1){
			break;
		}
	}
}
void solve(){
    cin>>n>>m>>k;
    for(int i=1;i<=m;i++){
		cin>>a[i].u>>a[i].v>>a[i].w;
	}
	kruskal();
	for(int i=1;i<=k;i++){
		cin>>c[i];
		for(int j=1;j<=n;j++){
			int w;
			cin>>w;
			a[++tot]={n+i,j,w};
		}
	}
	sort(a+1,a+tot+1,cmp);
	for(int s=0;s<(1<<k);s++){
		int sum=0;
		int num=0;
		for(int i=1;i<=k;i++){
			if(s>>(i-1)&1){
				num++;
				vis[i]=1;
				sum+=c[i];
			}else{
				vis[i]=0;
			}
		}
		for(int i=1;i<=n+k;i++){
			father[i]=i;
		}
		int to=0;
		for(int i=1;i<=tot;i++){
			int x=a[i].u;
			int y=a[i].v;
			if(x>n&&!vis[x-n])	continue;
			x=find(x);
			y=find(y);
			if(x!=y){
				to++;
				Union(x,y);
				sum+=a[i].w;
				if(to==n+num-1)	break;
			}
		}
		answer=min(answer,sum);
	}
	cout<<answer;
}
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int T=1;
    //cin>>T;
    while(T--) solve();
    return 0;
}