#include <bits/stdc++.h>
using std :: min;
const int INF = 999999;
int n,k,m,s,t,dist[101][101],c[101],a[101][101];
int main() {
  freopen("culture.in","r",stdin);
  freopen("culture.out","w",stdout);	
  scanf("%d%d%d%d%d",&n,&k,&m,&s,&t);
  for (int i = 1;i <= n;i++)
    for (int j = 1;j <= n;j++) dist[i][j] = INF;
  for (int i = 1;i <= n;i++) scanf("%d",&c[i]);
  for (int i = 1;i <= k;i++)
    for (int j = 1;j <= k;j++)
      scanf("%d",&a[i][j]);
  for (int i = 1;i <= m;i++) {
    int a1,b1,c1;
    scanf("%d%d%d",&a1,&b1,&c1);
    dist[a1][b1] = dist[b1][a1] = c1;
  }
  for (int i = 1;i <= n;i++)
    for (int j = 1;j <= n;j++)
      if (a[c[i]][c[j]]) dist[i][j] = INF;
  for (int k = 1;k <= n;k++)      //floyd
    for (int i = 1;i <= n;i++)
      for (int j = 1;j <= n;j++) dist[i][j] = min(dist[i][j],dist[i][k]+dist[k][j]);
  if (dist[s][t] == INF) printf("%d",-1);
  else printf("%d",dist[t][s]);
}