#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 17;
int n, m, q, lg, c[N], ans[N];
int r[N], d[N], p[20][N];
tuple <int, int, int> e[N];
vector <int> adj[N];
bool ex[N];
int root (int u)
{
if (u == r[u])
{
return u;
}
return r[u] = root(r[u]);
}
void join (int x, int y, int z)
{
x = root(x);
y = root(y);
++n, r[n] = n;
if (x == y)
{
ex[n] = 1, r[x] = n;
adj[n].push_back(x);
}
else
{
ex[n] = ex[x] | ex[y] | z;
r[x] = r[y] = n;
adj[n].push_back(x);
adj[n].push_back(y);
}
}
int lca (int u, int v)
{
if (d[u] < d[v])
{
swap (u, v);
}
for (int i = lg; i >= 0; --i)
{
if (d[p[i][u]] >= d[v])
{
u = p[i][u];
}
}
if (u == v)
{
return u;
}
for (int i = lg; i >= 0; --i)
{
if (p[i][u] != p[i][v])
{
u = p[i][u], v = p[i][v];
}
}
return p[0][u];
}
void dfs (int u, int pr)
{
d[u] = d[pr] + 1, p[0][u] = pr;
for (int i = 1; i <= lg; ++i)
{
p[i][u] = p[i - 1][p[i - 1][u]];
}
for (int v: adj[u])
{
if (v != pr)
{
dfs (v, u);
}
}
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> m;
lg = __lg(n + m);
for (int i = 1, u, v, w; i <= m; ++i)
{
cin >> u >> v >> w;
++u, ++v;
e[i] = {w, u, v};
}
for (int i = 1; i <= n; ++i)
{
r[i] = i;
}
sort (e + 1, e + m + 1);
for (int i = 1; i <= m; ++i)
{
auto [w, u, v] = e[i];
++c[u], ++c[v];
int z = (c[u] > 2) | (c[v] > 2);
join (u, v, z);
ans[n] = w;
}
for (int i = n; i >= 0; --i)
{
if (!d[i])
{
dfs (i, 0);
}
}
cin >> q;
while (q--)
{
int u, v;
cin >> u >> v;
++u, ++v;
int z = lca (u, v);
if (ex[z])
{
cout << ans[z] << "\n";
continue;
}
for (int i = lg; i >= 0; --i)
{
if (p[i][z] && !ex[p[i][z]])
{
z = p[i][z];
}
}
z = p[0][z];
if (!z)
{
cout << "-1\n";
continue;
}
cout << ans[z] << "\n";
}
}
Compilation message
/usr/bin/ld: /tmp/ccE5LzOg.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccYkgRSh.o:swap.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccE5LzOg.o: in function `main':
grader.cpp:(.text.startup+0x1c3): undefined reference to `init(int, int, std::vector<int, std::allocator<int> >, std::vector<int, std::allocator<int> >, std::vector<int, std::allocator<int> >)'
/usr/bin/ld: grader.cpp:(.text.startup+0x217): undefined reference to `getMinimumFuelCapacity(int, int)'
collect2: error: ld returned 1 exit status
