# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1258922 | khoile08 | Crocodile's Underground City (IOI11_crocodile) | C++17 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i = a; i <= b; i++)
#define FOD(i,a,b) for(int i = a; i >= b; i--)
//#define int long long
#define fi first
#define se second
#define pb push_back
#define ll long long
#define ull unsigned long long
#define db double
#define lcm(a,b) a / __gcd(a, b) * b
#define ii pair<int,int>
#define iii pair<int,pair<int,int>>
#define iv pair<pair<int,int>,pair<int,int>>
#define sq(a) (a) * (a)
#define MASK(i) (1LL << i)
#define task "task"
const int inf = 2e9;
const ll INF = 1e18;
const int mod = 1e9 + 7;
const int N = 1e5 + 5;
const int M = 1e6 + 5;
int n, m, k;
int R[M][2], L[M], P[N];
ll d[2][N];
vector<ii> g[N];
int travel_plan(int n, int m, int R[][2], int L[], int k, int P[]) {
priority_queue<ii,vector<ii>,greater<ii>> pq;
FOR(i, 0, n - 1) d[0][i] = d[1][i] = INF;
FOR(i, 0, m - 1) {
g[R[i][0]].pb({R[i][1], L[i]});
g[R[i][1]].pb({R[i][0], L[i]});
}
FOR(i, 0, k - 1) {
d[0][P[i]] = d[1][P[i]] = 0;
pq.push({0, P[i]});
}
while(!pq.empty()) {
int cost = pq.top().fi;
int u = pq.top().se;
pq.pop();
if(cost != d[1][u]) continue;
for(auto H : g[u]) {
int v = H.fi;
int w = H.se;
if(d[0][v] == cost + w && d[0][v] < d[1][v]) {
d[1][v] = d[0][v];
pq.push({d[1][v], v});
}
if(d[0][v] > cost + w) {
if(d[0][v] < d[1][v]) pq.push({d[0][v], v});
d[1][v] = d[0][v];
d[0][v] = cost + w;
}
else if(d[1][v] > cost + w) {
d[1][v] = cost + w;
pq.push({d[1][v], v});
}
}
}
return d[1][0];
}
int main() {
// if(fopen(task".inp", "r")) {
// freopen(task".inp", "r", stdin);
// freopen(task".out", "w", stdout);
// }
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> m >> k;
FOR(i, 0, m - 1) cin >> R[i][0] >> R[i][1] >> L[i];
FOR(i, 0, k - 1) cin >> P[i];
cout << travel_plan(n, m, R, L, k, P) << '\n';
}