#include <bits/stdc++.h>
using namespace std;
using ll = long long;
ll n, m, q, k, x, y, a, b, c, l;
vector< pair<ll, ll> > G[100000];
ll mx[100000], mxu[100000];
bool vis[100000];
void dfs(ll x, ll p) {
vis[x] = 1;
for (auto i : G[x]) {
if (i.first != p) {
dfs(i.first, x);
mx[x] = max(mx[x], mx[i.first] + i.second);
}
}
}
void dfsu(ll x, ll p) {
vector< pair<ll, ll> > v;
for (auto i : G[x]) {
if (i.first != p) {
v.push_back({mx[i.first] + i.second, i.first});
}
}
sort(v.rbegin(), v.rend());
for (auto i : G[x]) {
if (i.first != p) {
mxu[i.first] = mxu[x] + i.second;
if (v.size() != 1) {
if (v[0].second != i.first) {
mxu[i.first] = max(mxu[i.first], v[0].first + i.second);
}
else {
mxu[i.first] = max(mxu[i.first], v[1].first + i.second);
}
}
dfsu(i.first, x);
}
}
// cout << x << ' ' << mx[x] << ' ' << mxu[x] << '\n';
}
pair<int, int> dfsp(ll x, ll p) {
pair<int, int> pr = {max(mx[x], mxu[x]), x};
for (auto i : G[x]) {
if (i.first != p) {
pr = min(pr, dfsp(i.first, x));
}
}
return pr;
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
n = N;
m = M;
l = L;
for (int i = 0; i < m; i++) {
G[A[i]].push_back({B[i], T[i]});
G[B[i]].push_back({A[i], T[i]});
}
vector< pair<int, int> > vp;
for (int i = 0; i < n; i++) {
if (!vis[i]) {
dfs(i, -1);
dfsu(i, -1);
vp.push_back(dfsp(i, -1));
}
}
// for (auto i : vp) {
// cout << i.first << ' ' << i.second << '\n';
// }
sort(vp.rbegin(), vp.rend());
int ans = vp[0].first + vp[1].first + L;
if (vp.size() > 2) {
ans = max(ans, vp[1].first + vp[2].first + L * 2);
}
return ans;
}
Compilation message
/usr/bin/ld: /tmp/ccdrvdPW.o: in function `main':
grader.c:(.text.startup+0xd1): undefined reference to `travelTime'
collect2: error: ld returned 1 exit status
