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#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
using edge = tuple<int, int, int>;
const int NMAX = 15e3+2;
const int LMAX = 15;
int n,m,q,niv[NMAX],up[LMAX][NMAX],mx[LMAX][NMAX];
vector<edge> edges;
vector<pii> v[NMAX];
ifstream fin("radiatie.in");
ofstream fout("radiatie.out");
struct DSU {
int n;
vector<int> t, sz;
DSU(int _n){
n = _n;
t.resize(n+1);
sz.resize(n+1, 1);
for(int i = 1; i <= n; i++){
t[i] = i;
}
}
int root(int nod){
if(t[nod] == nod){
return nod;
}
return t[nod] = root(t[nod]);
}
void join(int x, int y){
x = root(x);
y = root(y);
if(sz[x] < sz[y]){
swap(x, y);
}
t[y] = x;
sz[x] += sz[y];
}
bool areJoined(int x, int y){
return root(x) == root(y);
}
};
void dfs(int nod, int tata = -1){
for(auto [fiu, cost]: v[nod]){
if(fiu == tata){
continue;
}
niv[fiu] = 1+niv[nod];
up[0][fiu] = nod;
mx[0][fiu] = cost;
for(int i = 1; i < LMAX; i++){
up[i][fiu] = up[i-1][up[i-1][fiu]];
mx[i][fiu] = max(mx[i-1][fiu], mx[i-1][up[i-1][fiu]]);
}
dfs(fiu, nod);
}
}
int maxSelf(int &a, int b){
a = max(a, b);
}
int query(int x, int y){
if(niv[y] < niv[x]){
swap(x, y);
}
int ans = 0;
int diff = niv[y]-niv[x];
for(int i = LMAX-1; i >= 0; i--){
if((diff>>i)&1){
maxSelf(ans, mx[i][y]);
y = up[i][y];
}
}
if(x == y){
return ans;
}
for(int i = LMAX-1; i >= 0; i--){
if(up[i][x] != up[i][y]){
maxSelf(ans, mx[i][x]);
maxSelf(ans, mx[i][y]);
x = up[i][x];
y = up[i][y];
}
}
maxSelf(ans, mx[0][x]);
maxSelf(ans, mx[0][y]);
return ans;
}
int main()
{
fin >> n >> m >> q;
for(int i = 1; i <= m; i++){
int x, y, c;
fin >> x >> y >> c;
edges.push_back({c, x, y});
}
sort(edges.begin(), edges.end());
DSU ds(n);
for(auto [cost, x, y]: edges){
if(!ds.areJoined(x, y)){
v[x].push_back({y, cost});
v[y].push_back({x, cost});
ds.join(x, y);
}
}
dfs(1);
while(q--){
int x, y;
fin >> x >> y;
fout << query(x, y) << "\n";
}
return 0;
}