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#include <bits/stdc++.h>
using namespace std;
ifstream f("radiatie.in");
ofstream g("radiatie.out");
const int NMAX = 15005;
const int LMAX = 16;
int sz[NMAX],link[NMAX],dist[NMAX],dp[LMAX][NMAX],c[LMAX][NMAX],n;
vector < tuple < int,int,int> > edges;
vector < pair < int, int> > v[NMAX];
int find(int x){
while(x != link[x])
x = link[x];
return x;
}
void unite(int x, int y){
x = find(x);
y = find(y);
if(sz[y] > sz[x])
swap(x,y);
sz[x] += sz[y];
link[y] = x;
}
void dfs(int nod){
for(auto it: v[nod]){
if(!dist[it.first]){
dist[it.first] = dist[nod] + 1;
dfs(it.first);
dp[0][it.first] = nod;
c[0][it.first] = it.second;
}
}
}
void buildDP(){
int i,j;
for(i = 1 ; (1 << i) <= n ; i++)
for(j = 1 ; j <= n ; j++){
dp[i][j] = dp[i - 1][dp[i - 1][j]];
c[i][j] = max(c[i - 1][j], c[i - 1][dp[i - 1][j]]);
}
}
int query(int x, int y){
if(dist[x] < dist[y])
swap(x,y);
int L1 = 1;
int L2 = 1;
while ( (1<<L1) < dist[x])
L1++;
while ( (1<<L2) < dist[y])
L2++;
int maxim = 0,i,j;
for(i = L1 ; i >= 0 ; i--)
if(dist[x] - (1 << i) >= dist[y]){
maxim = max(maxim, c[i][x]);
x = dp[i][x];
}
if(x == y)
return maxim;
for(i = L2 ; i >= 0 ; i--)
if(dist[x] - (1 << i) >= 0 && dp[i][x] != dp[i][y] ){
maxim = max(maxim, max(c[i][x], c[i][y]));
x = dp[i][x];
y = dp[i][y];
}
maxim = max(maxim, max(c[0][x], c[0][y]));
return maxim;
}
int main(){
int i,m,q,j;
f >> n >> m >> q;
for(i = 1 ; i <= n ; i++){
link[i] = i;
sz[i] = 1;
}
for(i = 1 ; i <= m ; i++){
int x,y,c;
f >> x >> y >> c;
edges.push_back(make_tuple(c,x,y));
}
sort(edges.begin(), edges.end());
for(auto it : edges){
int cost = get<0> (it);
int x = get<1> (it);
int y = get<2> (it);
if(find(x) != find(y)){
v[x].push_back(make_pair(y,cost));
v[y].push_back(make_pair(x,cost));
unite(x,y);
}
}
dfs(1);
buildDP();
for(i = 1 ; i <= q ; i++){
int x, y;
f >> x >> y;
g << query(x,y) << "\n";
}
return 0;
}