#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <unordered_set>
#include <vector>
#include <climits>
#include <list>
using namespace std;
using ll = long long;
using db = long double; // or double, if TL is tight
using llu = unsigned long long;
using str = string; // yay python!
// pairs
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using pdb = pair<db,db>;
#define mp make_pair
#define fr first
#define sc second
#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<db>;
using vs = V<str>;
using vpi = V<pii>;
using vpl = V<pll>;
using vpd = V<pdb>;
#define ms0(x) memset(x , 0, sizeof(x))
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
#define lb lower_bound
#define ub upper_bound
tcT> int lwb(V<T>& a, const T& b) { return int(lb(all(a),b)-bg(a)); }
tcT> int upb(V<T>& a, const T& b) { return int(ub(all(a),b)-bg(a)); }
// loops
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)
const int MOD = (int)1e9+7; // 998244353;
const int MX = (int)2e5+5;
const ll BIG = 1e18; // not too close to LLONG_MAX
const db PI = acos((db)-1);
inline namespace FileIO {
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void setIO(str s = "") {
cin.tie(0)->sync_with_stdio(0); // unsync C / C++ I/O streams
// cin.exceptions(cin.failbit);
// throws exception when do smth illegal
// ex. try to read letter into int
if (sz(s)) setIn(s+".in"), setOut(s+".out"); // for old USACO
}
}
const int dx[4] = {0,1,0,-1};
const int dy[4] = {-1,0,1,0};
int travel_plan(int N, int M, int R[][2], int L[], int K, int P[]){
ll dp[N + 1];
ll dist[N + 1];
for (int i = 0; i<=N; i++){
dp[i]=1e18;
dist[i] = 1e18;
}
priority_queue<pair<ll, int>>q;
for (int i = 0; i < K; i++){
dp[P[i]] = 0;
q.push(mp(0,P[i]));
}
vector<pair<int,int>>edges[N + 1];
for (int i = 0; i<M; i++){
edges[R[i][0]].pb(mp(R[i][1], L[i]));
edges[R[i][1]].pb(mp(R[i][0], L[i]));
}
while(!q.empty()){
ll distt = -q.top().fr;
int node = q.top().sc;
q.pop();
if (dp[node] != distt)continue;
//cout<<node<<" "<<distt<<endl;
for (auto edge : edges[node]){
ll nx = dp[edge.fr];
if (nx > distt + edge.sc){
dp[edge.fr] = distt + edge.sc;
q.push(mp( - (distt + edge.sc ), edge.fr));
}
}
}
priority_queue<pair<ll,int>>traverse;
traverse.push(mp(0,0));
ll ans = 1e9 + 1;
dist[0]=0;
int visited[N + 1];
memset(visited, 0, sizeof(visited));
while(!traverse.empty()){
ll distt = -traverse.top().fr;
int node = traverse.top().sc;
visited[node] = 1;
traverse.pop();
//cout<<node<<" "<<distt<<endl;
if (distt != dist[node])continue;
ll smallest = 1e18;
ll smallest_ind = -1;
ll second_ind = -1;
ll second = 1e18;
for (int i = 0; i< (int) edges[node].size(); i++){
if (visited[edges[node][i].fr])continue;
pair<int,ll>edge = edges[node][i];
if (dp[edge.fr] + edge.sc < smallest){
swap(second_ind, smallest_ind);
swap(smallest, second);
smallest = dp[edge.fr] + edge.sc;
smallest_ind = i;
}else if (dp[edge.fr] + edge.sc< second){
second = dp[edge.fr] + edge.sc;
second_ind = i;
}
}
if (second_ind == -1 || smallest_ind == -1){
//cout<<"no solution";
continue;
}
cout<<edges[node][smallest_ind].fr<<" "<<edges[node][second_ind].fr<<endl;
if (dist[edges[node][second_ind].fr] > distt + edges[node][second_ind].sc){
dist[edges[node][second_ind].fr] = distt + edges[node][second_ind].sc;
traverse.push(mp(-dist[edges[node][second_ind].fr], edges[node][second_ind].fr));
}
}
for (int i = 0; i<K; i++){
ans = min(ans, dist[P[i]]);
}
return (int)ans;
}
int main() {
setIO("");
int N, M, K;
cin >> N >> M >> K;
int R[M][2];
int L[M];
int P[K];
for (int i = 0; i<M; i++){
cin >> R[i][0] >> R[i][1] >> L[i];
}
for (int i = 0; i<K; i++){
cin >> P[i];
}
cout<<travel_plan(N,M,R,L,K,P);
return 0;
}
Compilation message
crocodile.cpp: In function 'void FileIO::setIn(str)':
crocodile.cpp:82:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
82 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
crocodile.cpp: In function 'void FileIO::setOut(str)':
crocodile.cpp:83:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
83 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccTfbFSQ.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccuql15S.o:crocodile.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status