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#include<bits/stdc++.h>
using namespace std;
const int V=1e5+5;
int to[V<<1],nex[V<<1],head[V],w[V],cnt,n;
void ini(){cnt=-1;for(int i=0;i<=n;i++) head[i]=-1;}
void addEdge(int u,int v){to[++cnt]=v;nex[cnt]=head[u];head[u]=cnt;}
int dep[V],dad[V],siz[V],son[V],chain[V],dfn[V];
void dfs1(int u,int father){
dep[u]=dep[father]+1;
dad[u]=father, siz[u]=1, son[u]=-1;
for(int i=head[u];~i;i=nex[i]){
int v=to[i];
if(v==father)continue;
dfs1(v,u);
siz[u]+=siz[v];
if(son[u]==-1||siz[son[u]]<siz[v]) son[u]=v;
}
}
void dfs2(int u,int s,int&step){
dfn[u]=++step;
chain[u]=s;
if(son[u]!=-1) dfs2(son[u],s,step);
for(int i=head[u];~i;i=nex[i]){
int v=to[i];
if(v!=son[u]&&v!=dad[u]) dfs2(v,v,step);
}
}
int lca(int x,int y){
int res=0;
while(chain[x]!=chain[y]){
if(dep[chain[x]]<dep[chain[y]]) swap(x,y);
x=dad[chain[x]];
}
if(dep[x]>dep[y]) swap(x,y);
return x;
}
int f[V];
int find(int x){return x==f[x]?x:f[x]=find(f[x]);}
bool cmpVec(const vector<int>&a,const vector<int>&b){return a[2]<b[2];}
void reBuildTree(vector<vector<int> >&edges){
sort(edges.begin(),edges.end(),cmpVec);
ini();
for(int i=0;i<=n*2;i++) f[i]=i;
for(int i=0;i<edges.size();i++){
int u=edges[i][0];
int v=edges[i][1];
if(find(u)==find(v)) continue;
head[++n]=-1;
addEdge(n,f[u]);
addEdge(n,f[v]);
w[n]=edges[i][2];
f[f[u]] = f[f[v]] = n;
}
}
int main(){
int m,k;
cin>>n>>m>>k;
vector<vector<int> > edges(m,vector<int>(3));
for(int i=0;i<m;i++) cin>>edges[i][0]>>edges[i][1]>>edges[i][2];
reBuildTree(edges);
int step=0;
dfs1(n,0);
dfs2(n,n,step);
while(k--){
int x,y;
cin>>x>>y;
cout<<w[lca(x,y)]<<endl;
}
}
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