이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define mp make_pair
#define pb push_back
#define sz(x) ((int)((x).size()))
#define all(x) (x).begin(),(x).end()
#define deb(x) cerr << "(" << #x << " = " << x << ")\n";
typedef long long ll;
typedef pair<int,int> PII;
typedef pair<ll,ll> PLL;
typedef vector<int> VI;
const int MAXN = 100100;
const int MAXA = 100100;
const int MAXB = 100100;
const int INF = 1e9;
const int LOGN = 17;
int n, m, A, B;
vector < PII > g[MAXN];
vector < int > gr[MAXN];
int bad[MAXA];
PII ev[MAXB];
int id[MAXN];
int sh[MAXN];
set < PII > q;
inline bool cmp(int i, int j) {
return sh[i] > sh[j];
}
void dijkstra() {
while(!q.empty()) {
int v = q.begin() -> S;
q.erase(q.begin());
for(int i = 0; i < sz(g[v]); ++i) {
int to = g[v][i].F;
int w = g[v][i].S;
if(sh[to] > sh[v] + w) {
q.erase( mp(sh[to], to) );
sh[to] = sh[v] + w;
q.insert( mp(sh[to], to) );
}
}
}
}
int p[MAXN];
int sz[MAXN];
inline int Find(int v) {
return v == p[v] ? v : p[v] = Find(p[v]);
}
inline void Uni(int a, int b) {
if(sz[a] >= sz[b])
p[b] = a, sz[a] += sz[b];
else
p[a] = b, sz[b] += sz[a];
}
int tin[MAXN];
int tout[MAXN];
int timer;
int up[MAXN][LOGN + 5];
int mn[MAXN][LOGN + 5];
void dfs(int v, int p = 0) {
tin[v] = ++timer;
up[v][0] = p;
mn[v][0] = sh[v];
for(int i = 1; i <= LOGN; ++i) {
up[v][i] = up[up[v][i-1]][i-1];
mn[v][i] = min(mn[v][i-1], mn[up[v][i-1]][i-1]);
}
for(int to : gr[v]) {
if(to != p) {
dfs(to, v);
}
}
tout[v] = ++timer;
}
inline bool upper(int a, int b) {
return tin[a] <= tin[b] && tout[a] >= tout[b];
}
inline int lca(int a, int b) {
if(upper(a, b)) return a;
if(upper(b, a)) return b;
for(int i = LOGN; i >= 0; --i) {
if(up[a][i] != 0 && !upper(up[a][i], b)) {
a = up[a][i];
}
}
return up[a][0];
}
int calc(int a, int b) {
if(a == b) return sh[a];
int c = lca(a, b);
int res = INF;
for(int i = LOGN; i >= 0; --i) {
if(up[a][i] != 0 && !upper(up[a][i], c)) {
res = min(res, mn[a][i]);
a = up[a][i];
}
if(up[b][i] != 0 && !upper(up[b][i], c)) {
res = min(res, mn[b][i]);
b = up[b][i];
}
}
res = min(res, mn[a][0]);
res = min(res, mn[b][0]);
res = min(res, sh[c]);
return res;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> m;
for(int i = 1; i <= m; ++i) {
int x, y, z;
cin >> x >> y >> z;
g[x].pb( mp(y, z) );
g[y].pb( mp(x, z) );
}
for(int i = 1; i <= n; ++i) {
sh[i] = INF;
id[i] = i;
}
cin >> A;
for(int i = 1; i <= A; ++i) {
cin >> bad[i];
q.insert( mp(sh[bad[i]] = 0, bad[i]) );
}
dijkstra();
sort(id + 1, id + n + 1, &cmp);
for(int i = 1; i <= n; ++i) {
p[i] = i, sz[i] = 1;
}
for(int it = 1; it <= n; ++it) {
int i = id[it];
for(PII j : g[i]) {
if(sh[j.F] >= sh[i] && Find(i) != Find(j.F)) {
Uni(Find(i), Find(j.F));
gr[i].pb(j.F);
gr[j.F].pb(i);
}
}
}
sh[0] = INF;
dfs(1);
ll ans = 0;
cin >> B;
for(int i = 1; i <= B; ++i) {
int x, y;
cin >> x >> y;
cout << calc(x, y) << endl;
}
return 0;
}
컴파일 시 표준 에러 (stderr) 메시지
plan.cpp: In function 'int main()':
plan.cpp:166:8: warning: unused variable 'ans' [-Wunused-variable]
ll ans = 0;
^~~
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