城市平亂
#include<cstdio>
#include<cstring>
#include<vector>
#define N 1001
#define INF 0x7FFFFFFF
using namespace std;
struct node{
int v, w;
node(int a, int b){
v = a; w = b;
}
};
vector<node*> G[N];
int dist[N], Army[101];
bool vis[N];
int m, n, p, q;
void dijkstra(){
int i, j, u, w, cur = q;
dist[cur] = 0;
while(!vis[cur]){ // 當還有節點沒有被訪問時
vis[cur] = 1;
for(i = 0; i < G[cur].size(); i++){ // 遍歷cur節點的鄰接點
u = G[cur][i]->v; // 鄰接點的節點號
w = G[cur][i]->w; // 權重
if(dist[cur] + w < dist[u]) // 更新鄰接點最短路徑權值
dist[u] = dist[cur] + w;
}
int min_cost = INF;
for(i = 1; i <= m; i++){ // 查找未訪問的最小總權值節點
if(!vis[i] && dist[i] < min_cost){
min_cost = dist[i];
cur = i;
}
}
}
}
int main(){
int i, j, k, a, b, c;
freopen("data.in", "r", stdin);
scanf("%d", &k);
while(k--){
scanf("%d%d%d%d", &n, &m, &p, &q);
for(i = 0; i <= m; i++){ // 初始化
G[i].clear();
dist[i] = INF;
vis[i] = 0;
}
for(i = 0; i < n; i++) scanf("%d", &Army[i]);
while(p--){
scanf("%d%d%d", &a, &b, &c);
G[a].push_back(new node(b, c));
G[b].push_back(new node(a, c));
}
dijkstra();
int ans = INF;
for(i = 0; i < n; i++){
if(ans > dist[Army[i]])
ans = dist[Army[i]];
}
printf("%d\n", ans);
}
return 0;
}