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#include <fstream>
#include <vector>
#include <algorithm>
#define NMAX 15005
#define LOG_MAX 15
using namespace std;
ifstream in("radiatie.in");
ofstream out("radiatie.out");
struct edge{
int x, y, cost;
};
struct ok{
int vecin, cost;
};
struct lca{
int t, maxx;
};
bool cmp(edge a, edge b)
{
return a.cost < b.cost;
}
vector <edge> edges;
int father[NMAX], level[NMAX];
vector <int> adj[NMAX];
lca table[NMAX][LOG_MAX];
lca tata[NMAX];
int f(int x)
{
if (father[x] == x)
return x;
return father[x] = f(father[x]);
}
void unite(int x, int y)
{
int fx = f(x), fy = f(y);
father[fy] = fx;
}
void dfs(int node, int last)
{
level[node] = level[last] + 1;
for (int i = 0; i < adj[node].size(); ++i)
{
int vecin = adj[node][i];
if (vecin != last)
dfs(vecin, node);
}
}
int query(int a, int b)
{
if (level[a] > level[b])
swap(a, b);
int maxim = -1;
while (level[a] < level[b])
{
for (int lvl = LOG_MAX - 1; lvl >= 0; --lvl)
{
if (level[table[b][lvl].t] >= level[a])
{
maxim = max(maxim, table[b][lvl].maxx);
b = table[b][lvl].t;
}
}
}
if (a != b)
{
for (int lvl = LOG_MAX - 1; lvl >= 0; --lvl)
{
if (table[a][lvl].t != table[b][lvl].t)
{
maxim = max(maxim, table[a][lvl].maxx);
maxim = max(maxim, table[b][lvl].maxx);
a = table[a][lvl].t;
b = table[b][lvl].t;
}
}
maxim = max(maxim, table[a][0].maxx);
maxim = max(maxim, table[b][0].maxx);
a = table[a][0].t;
b = table[b][0].t;
}
return maxim;
}
int main()
{
int n, m, k, i, j, a, b, c, cnt = 0;
in >> n >> m >> k;
for (i = 1; i <= m; ++i)
father[i] = i;
for (i = 1; i <= m; ++i)
{
in >> a >> b >> c;
edges.push_back({a, b, c});
}
sort (edges.begin(), edges.end(), cmp);
for (i = 0; i < m; ++i)
{
int x = edges[i].x;
int y = edges[i].y;
int cost = edges[i].cost;
if (f(x) != f(y))
{
unite(x, y);
adj[x].push_back(y);
adj[y].push_back(x);
tata[y].t = x;
tata[y].maxx = cost;
}
}
int root;
for (i = 1; i <= n; ++i)
{
if (tata[i].t == 0)
root = i;
table[i][0].t = tata[i].t;
table[i][0].maxx = tata[i].maxx;
}
for (int lvl = 1; lvl < LOG_MAX; ++lvl)
{
for (i = 1; i <= n; ++i)
{
table[i][lvl].t = table[table[i][lvl - 1].t][lvl - 1].t;
if (table[i][lvl - 1].maxx && table[table[i][lvl - 1].t][lvl - 1].maxx)
table[i][lvl].maxx = max(table[i][lvl - 1].maxx, table[table[i][lvl - 1].t][lvl - 1].maxx);
}
}
dfs(root, 0);
for (i = 1; i <= k; ++i)
{
in >> a >> b;
out << query(a, b) << '\n';
}
return 0;
}