#include <dreaming.h>
#include <iostream>
#include <tuple>
#include <vector>
using namespace std;
#define rep(i, a, b) for (auto i = (a); i < (b); ++i)
#define trav(x, v) for (auto &x : v)
#define eb(x...) emplace_back(x)
using pii = pair<int, int>;
template<class T> bool ckmin(T& a, T b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, T b) { return a < b ? a = b, 1 : 0; }
#define int long long
constexpr int N = 1 << 17;
vector<pii> g[N];
int d[N], p[N], a;
bool vis[N];
void dfs(int u, int p = -1) {
if (d[u] > d[a]) a = u;
::p[u] = p;
vis[u] = true;
trav(e, g[u]) {
int v, w; tie(v, w) = e;
if (v == p) continue;
d[v] = d[u] + w;
dfs(v, u);
}
}
signed travelTime(int n, int m, int l, int A[], int B[], int T[]) {
rep(i, 0, m) {
g[A[i]].eb(B[i], T[i]);
g[B[i]].eb(A[i], T[i]);
}
int ans = 0, one = 0, two = 0;
rep(u, 0, n) {
if (vis[u]) continue;
a = u; d[u] = 0; dfs(u);
d[a] = 0; dfs(a);
int e = d[a]; ckmax(ans, d[a]);
for (int v = a; p[v] != -1; v = p[v])
ckmin(e, max(d[a] - d[v], d[v]));
if (one <= e) two = one, one = e;
else if (two < e) two = e;
}
return two ? max(ans, one + two + l) : ans;
}
Compilation message
/tmp/ccn9dGnz.o: In function `main':
grader.c:(.text.startup+0xa2): undefined reference to `travelTime'
collect2: error: ld returned 1 exit status
