#include<cstring>
#include<cstdio>
#include<queue>

using namespace std;

const int INF = 0x7fffffff;
const int MAXN = 100005;
const int MAXM = 300005;
int n, m, k, u, v, p, spe[MAXN], S[MAXN], dexs, T[MAXN], dext, ans = INF;
bool b[MAXN];

inline int read(){
    int x = 0;
    bool fl = 1;
    char ch = getchar();
    while(ch < '0' && ch > '9'){
        if(ch == '-')   fl = 0;
        ch = getchar();
    }
    while(ch >= '0' && ch <= '9'){
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    return fl ? x : -x;
}

struct Node{
    int dis, num;
    bool operator < (const Node& a) const{
        return a.dis < dis;
    }
};

struct Edge{
    int nxt, to, dis;
}edge[MAXM];

int head[MAXN], edge_num;
void add_edge(int from, int to, int dis){
    edge[++edge_num].nxt = head[from];
    edge[edge_num].to = to;
    edge[edge_num].dis = dis;
    head[from] = edge_num;
}

int dis[MAXN];
bool vis[MAXN];
void dijkstra(){
    priority_queue<Node> q;
    for(int i = 1; i <= n; i++) dis[i] = INF, vis[i] = 0;
    for(int i = 1; i <= dexs; i++){
        q.push((Node){0, S[i]});
        dis[S[i]] = 0;
    }
    while(!q.empty()){
        Node x = q.top(); q.pop();
        int cur = x.num;
        if(vis[cur])    continue;
        vis[cur] = 1;
        for(int i = head[cur]; i; i = edge[i].nxt){
            if(dis[cur] != INF && dis[edge[i].to] > dis[cur] + edge[i].dis){
                dis[edge[i].to] = dis[cur] + edge[i].dis;
                q.push((Node){dis[edge[i].to], edge[i].to});
            }
        }
    }
}

int main(){
//freopen("Graph.in", "r", stdin);
//freopen("Graph.out", "w", stdout);
    n = read(), m = read(), k = read();
    for(int i = 1; i <= m; i++){
        u = read(), v = read(), p = read();
        add_edge(u, v, p);
    }
    for(int i = 1; i <= k; i++) spe[i] = read();
    int a = 16;
    while(a!=-1){
        memset(S, 0, sizeof S); dexs = 0;
        memset(b, 0, sizeof b);
        for(int i = 1; i <= k; i++){
            int temp = (spe[i]>>a) & 1;
            if(temp)    S[++dexs] = spe[i];
            else    b[spe[i]] = 1;
        }
        dijkstra();
        for(int i = 1; i <= n; i++)
            if(b[i])    ans = min(ans, dis[i]);
        memset(S, 0, sizeof S); dexs = 0;
        memset(T, 0, sizeof T); dext = 0;
        memset(b, 0, sizeof b);
        for(int i = 1; i <= k; i++){
            int temp = (spe[i]>>a) & 1;
            if(temp)    T[++dext] = spe[i], b[spe[i]] = 1;
            else    S[++dexs] = spe[i];
        }
        dijkstra();
        for(int i = 1; i <= n; i++)
            if(b[i])    ans = min(ans, dis[i]);
        a--;
    }
    printf("%d", ans);
    return 0;
}

#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<queue>

using namespace std;

const int INF = 0x7fffffff;
const int MAXN = 100005;
const int MAXM = 300005;
int n, m, k, u, v, p, spe[MAXN], S[MAXN], dexs, T[MAXN], dext, ans = INF;
bool b[MAXN];

inline int read(){
    int x = 0;
    bool fl = 1;
    char ch = getchar();
    while(ch < '0' && ch > '9'){
        if(ch == '-')   fl = 0;
        ch = getchar();
    }
    while(ch >= '0' && ch <= '9'){
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    return fl ? x : -x;
}

struct Edge{
    int nxt, to, dis;
}edge[MAXM];

int head[MAXN], edge_num;
inline void add_edge(int from, int to, int dis){
    edge[++edge_num].nxt = head[from];
    edge[edge_num].to = to;
    edge[edge_num].dis = dis;
    head[from] = edge_num;
}

int dis[MAXN];
bool inq[MAXN];
inline void spfa(){
    for(int i = 1; i <= n; i++) dis[i] = INF;
    queue<int> q;
    for(int i = 1; i <= dexs; i++){
        q.push(S[i]);
        inq[S[i]] = 1;
        dis[S[i]] = 0;
    }
    while(!q.empty()){
        int cur = q.front(); q.pop(); inq[cur] = 0;
        for(int i = head[cur]; i; i = edge[i].nxt){
            if(dis[cur] < INF && dis[edge[i].to] > dis[cur] + edge[i].dis){
                dis[edge[i].to] = dis[cur] + edge[i].dis;
                if(!inq[edge[i].to]){
                    q.push(edge[i].to);
                    inq[edge[i].to] = 1;
                }
            }
        }
    }
}

int main(){
//freopen("Graph.in", "r", stdin);
//freopen("Graph.out", "w", stdout);
    srand(423186579);
    n = read(), m = read(), k = read();
    for(int i = 1; i <= m; i++){
        u = read(), v = read(), p = read();
        add_edge(u, v, p);
    }
    for(int i = 1; i <= k; i++) spe[i] = read();
    random_shuffle(spe+1, spe+k+1);
    int a = 16;
    while(a!=-1){
        memset(S, 0, sizeof S); dexs = 0;
        memset(T, 0, sizeof T); dext = 0;
        memset(b, 0, sizeof b);
        for(int i = 1; i <= k; i++){
            int temp = (spe[i]>>a) & 1;
            if(temp)    S[++dexs] = spe[i];
            else    T[++dext] = spe[i], b[spe[i]] = 1;
        }
        spfa();
        for(int i = 1; i <= n; i++)
            if(b[i])    ans = min(ans, dis[i]);
        memset(S, 0, sizeof S); dexs = 0;
        memset(T, 0, sizeof T); dext = 0;
        memset(b, 0, sizeof b);
        for(int i = 1; i <= k; i++){
            int temp = (spe[i]>>a) & 1;
            if(temp)    T[++dext] = spe[i], b[spe[i]] = 1;
            else    S[++dexs] = spe[i];
        }
        spfa();
        for(int i = 1; i <= n; i++)
            if(b[i])    ans = min(ans, dis[i]);
        a--;
    }
    printf("%d", ans);
    return 0;
}