1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
package com.hgs.atcoder.abc.contest277.e;
/**
* @author youtsuha
* @version 1.0
* Create by 2022/11/12 19:58
*/
import java.util.*;
import java.io.*;
public class Main {
static FastScanner cin;
static PrintWriter cout;
static int [][] dp;
private static void init()throws IOException {
cin = new FastScanner(System.in);
cout = new PrintWriter(System.out);
}
private static void close(){
cout.close();
}
static int n, m, k;
static class node{
int a, b, c;
//[]
public node(int a, int b, int c) {
this.a = a;
this.b = b;
this.c = c;
}
}
static List<node> e[];
static int ans = (int) 1e9;
static int inf = (int) 1e9;
static boolean isSwitch[];
//
static boolean dfs(int x, int fa, int rot, int dep){
//
//
}
private static void sol()throws IOException {
n = cin.nextInt(); m = cin.nextInt(); k = cin.nextInt();
dp = new int[n][2];
//
Arrays.fill(dp[0],inf);
//
Arrays.fill(dp[1],inf);
for(int j = 0; j < 2; j ++ ) {
for(int i = 0; i < n; i ++ ){
//cout.print(dp[i][j] + " ");
dp[i][j] = inf;
}
//
cout.println("");
}
e = new ArrayList[n];
isSwitch = new boolean[n];
for(int i = 0; i < n; i ++ ) {
e[i] = new ArrayList<>();
}
for(int i = 0; i < m; i ++ ) {
int a = cin.nextInt(), b = cin.nextInt(), c = cin.nextInt();
a--; b--;
e[a].add(new node(b,c,0));
e[b].add(new node(a,c,0));
}
for(int i = 0; i < k; i ++ ) {
int x = cin.nextInt(); x--;
isSwitch[x] = true;
}
//
dfs(0,-1,0, 0);
PriorityQueue<node> que = new PriorityQueue<>((a,b)->a.c - b.c);
dp[0][0] = 0;
que.add(new node(0,0,0));
while(!que.isEmpty()){
int x = que.peek().a, d = que.peek().c, rot=
que.peek().b;
que.poll();
if(dp[x][rot] > d) {
continue;
}
for(int i = 0; i < e[x].size(); i ++ ) {
int v = e[x].get(i).a, p = e[x].get(i).b;
int nxt = (p + rot) % 2;
if(nxt % 2 == 1){
if(dp[v][rot] > d + 1){
dp[v][rot] = Math.min(dp[v][rot], d + 1);
que.add(new node(v,rot,d+1));
}
}else if(isSwitch[x]){
nxt = (rot + 1) % 2;
if(dp[v][nxt] > d + 1){
dp[v][nxt] = Math.min(dp[v][nxt], d + 1);
que.add(new node(v,nxt, d + 1));
}
}
}
}
int ans = inf;
if(dp[n-1][0] != inf) {
ans = Math.min(ans, dp[n-1][0]);
}if(dp[n-1][1] != inf) {
ans = Math.min(ans, dp[n-1][1]);
}
if(ans == inf) {
cout.println(-1);
}else {
cout.println(ans);
}
}
public static void main(String[] args) throws IOException {
init();
sol();
close();
}
}
class FastScanner {
BufferedReader br;
StringTokenizer st = new StringTokenizer("");
public FastScanner(InputStream s) {
br = new BufferedReader(new InputStreamReader(s));
}
public FastScanner(String s) throws FileNotFoundException {
br = new BufferedReader(new FileReader(new File(s)));
}
public String next() throws IOException {
while (!st.hasMoreTokens()){
try {
st = new StringTokenizer(br.readLine());
} catch (IOException e) { e.printStackTrace(); }
}
return st.nextToken();
}
public int nextInt() throws IOException {
return Integer.parseInt(next());
}
public long nextLong() throws IOException {
return Long.parseLong(next());
}
public double nextDouble() throws IOException {
return Double.parseDouble(next());
}
}