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#include <fstream>
#include <vector>
#include <algorithm>
#include <tuple>
using namespace std;
ifstream cin("radiatie.in");
ofstream cout("radiatie.out");
struct muchie
{
int node1, node2, cost;
bool operator<(const muchie& temp) const
{
return cost < temp.cost;
}
};
struct ceva
{
int node, cost;
};
int n, m, q;
vector<vector<ceva>> adj;
vector<int> parent;
vector<int> rang;
int root(int x)
{
int repX;
for (repX = x; repX != parent[repX]; repX = parent[repX]);
return repX;
}
void unire(int x, int y)
{
int repX = root(x);
int repY = root(y);
if (repX == repY) return;
if (rang[repX] > rang[repY]) parent[repY] = repX;
else if (rang[repY] > rang[repX]) parent[repX] = repY;
else
{
rang[repX]++;
parent[repY] = repX;
}
}
vector<int> depth;
int rmq[15][15001];
int ancest[15][15001];
void dfs(int node, int parent)
{
for (auto pula : adj[node])
{
int vecin = pula.node;
int cost = pula.cost;
if (vecin == parent) continue;
depth[vecin] = depth[node] + 1;
rmq[0][vecin] = cost;
ancest[0][vecin] = node;
for (int e = 1; e <= 14; e++)
{
if (ancest[e - 1][ancest[e - 1][vecin]] == 0)
break;
ancest[e][vecin] = ancest[e - 1][ancest[e - 1][vecin]];
rmq[e][vecin] = max(rmq[e - 1][vecin], rmq[e - 1][ancest[e - 1][vecin]]);
}
dfs(vecin, node);
}
}
pair<int, int> kth(int u, int k) {
pair<int, int> res(u, 0);
for (int p = 0; (1 << p) <= k; ++p) {
if ((k >> p) & 1) {
res.second = max(res.second, rmq[p][res.first]);
res.first = ancest[p][res.first];
}
}
return res;
}
int query(int u, int v) {
if (depth[u] > depth[v]) {
swap(u, v);
}
int ans = 0;
if (depth[u] != depth[v]) {
tie(v, ans) = kth(v, depth[v] - depth[u]);
}
if (u == v) {
return ans;
}
for (int p = 15; p >= 0; --p) {
if (ancest[p][u] != ancest[p][v]) {
ans = max({ ans, rmq[p][u], rmq[p][v] });
u = ancest[p][u];
v = ancest[p][v];
}
}
return max({ ans, rmq[0][u], rmq[0][v] });
}
int main()
{
cin >> n >> m >> q;
vector<muchie> muc;
muc.resize(m + 1);
for (int i = 1; i <= m; i++)
{
int x, y, cost;
cin >> x >> y >> cost;
muc[i] = { x, y, cost };
}
sort(muc.begin() + 1, muc.begin() + m + 1);
parent.resize(m + 1), rang.resize(m + 1);
for (int i = 1; i <= m; i++)
{
parent[i] = i;
rang[i] = 1;
}
adj.resize(n + 1);
for (int i = 1; i <= m; i++)
{
int node1 = muc[i].node1;
int node2 = muc[i].node2;
int cost = muc[i].cost;
if (root(node1) != root(node2))
{
adj[node1].push_back({ node2, cost });
adj[node2].push_back({ node1, cost });
unire(node1, node2);
}
}
depth.resize(n + 1);
dfs(1, -1);
for (int i = 1; i <= q; i++)
{
int x, y;
cin >> x >> y;
cout << query(x, y) << '\n';
}
}