const int M=12005;struct node
{int v,w,next;
};node edges[M<<1];
int head[M],eNum;void add(int u,int v,int w)
{edges[eNum].v=v;edges[eNum].w=w;edges[eNum].next=head[u];head[u]=eNum++;
}int n,m;
int color[M];int fa[M][20];
int d[M],dep[M];int visit[M];queue<int> Q;void init()
{Q.push(1);visit[1]=1;while(!Q.empty()){int u=Q.front();Q.pop();for(int i=head[u];i!=-1;i=edges[i].next){int v=edges[i].v;int w=edges[i].w;if(!visit[v]){fa[v][0]=u;d[v]=d[u]+w;dep[v]=dep[u]+1;Q.push(v);visit[v]=1;}}}for(int i=1;i<20;i++) for(int j=1;j<=n;j++){fa[j][i]=fa[fa[j][i-1]][i-1];}
}int calLca(int u,int v)
{if(dep[u]<dep[v]) swap(u,v);int x=dep[u]-dep[v];for(int i=0;i<20;i++) if(x&(1<<i)) u=fa[u][i];if(u==v) return u;for(int i=19;i>=0;i--){if(fa[u][i]&&fa[v][i]&&fa[u][i]!=fa[v][i]){u=fa[u][i];v=fa[v][i];}}return fa[u][0];
}int calDis(int u,int v)
{int lca=calLca(u,v);return d[u]+d[v]-d[lca]*2;
}int sonNum[M];int nodeSum;int arr[M],arrNum;void dfs(int u,int pre)
{arr[++arrNum]=u;nodeSum++;sonNum[u]=1;for(int i=head[u];i!=-1;i=edges[i].next){int v=edges[i].v;if(v!=pre&&!visit[v]){dfs(v,u);sonNum[u]+=sonNum[v];}}
}int calCenter(int u)
{nodeSum=0; arrNum=0;dfs(u,0);int ans=u,Min=INF;for(int i=1;i<=arrNum;i++){int u=arr[i];int tmp=max(sonNum[u],nodeSum-sonNum[u]);if(tmp<Min) Min=tmp,ans=u;}return ans;
}struct NODE
{multiset<int> S,p;int getAns(){if(p.size()<2) return INF;int Min1=*p.begin();multiset<int>::iterator it=p.begin();it++;int Min2=*it;return Min1+Min2;}void del(int x){p.erase(p.find(x));}
};map<int,NODE> mp[M];
map<int,NODE>::iterator it;int inq[M],KK;
int dis[M];
int parent[M];int DFS(int root)
{root=calCenter(root);Q.push(root);KK++;inq[root]=KK;dis[root]=0;while(!Q.empty()){int u=Q.front();Q.pop();int c=color[u];if(mp[root].count(c)){mp[root][c].p.insert(dis[u]);}else{NODE tmp;tmp.p.insert(dis[u]);mp[root][c]=tmp;}for(int i=head[u];i!=-1;i=edges[i].next){int v=edges[i].v;int w=edges[i].w;if(!visit[v]&&KK!=inq[v]){inq[v]=KK;dis[v]=dis[u]+w;Q.push(v);}}}for(it=mp[root].begin();it!=mp[root].end();it++){NODE tmp=it->second;it->second.S.insert(tmp.getAns());}visit[root]=1;for(int i=head[root];i!=-1;i=edges[i].next){int v=edges[i].v;if(!visit[v]){v=DFS(v);for(it=mp[v].begin();it!=mp[v].end();it++){int c=it->first;int w=*(it->second.S.begin());mp[root][c].S.insert(w);}parent[v]=root;}}return root;
}int root;multiset<int> SS;void Add(int u,int c,int dis)
{if(mp[u].count(c)){mp[u][c].p.insert(dis);}else{NODE tmp;tmp.p.insert(dis);mp[u][c]=tmp;}
}int st[M],stTop;void setDel(multiset<int> &S,int x)
{multiset<int>::iterator it=S.find(x);if(it!=S.end()) S.erase(it);
}void del(int u,int c)
{setDel(SS,*mp[root][c].S.begin());int curNode=u;stTop=0;while(curNode) st[++stTop]=curNode,curNode=parent[curNode];for(int i=stTop;i>1;i--){int u=st[i];int v=st[i-1];setDel(mp[u][c].S,*mp[v][c].S.begin());}curNode=u;while(curNode){int p=parent[curNode];setDel(mp[curNode][c].S,mp[curNode][c].getAns());mp[curNode][c].del(calDis(u,curNode));mp[curNode][c].S.insert(mp[curNode][c].getAns());if(p){mp[p][c].S.insert(*(mp[curNode][c].S.begin()));}curNode=p;}SS.insert(*mp[root][c].S.begin());
}void upd(int u,int c)
{if(mp[root].count(c)){setDel(SS,*mp[root][c].S.begin());}int curNode=u;stTop=0;while(curNode) st[++stTop]=curNode,curNode=parent[curNode];for(int i=stTop;i>1;i--){int u=st[i];int v=st[i-1];if(!mp[v].count(c)) break;setDel(mp[u][c].S,*mp[v][c].S.begin());}for(int i=1;i<=stTop;i++){int u=st[i];if(mp[u].count(c)){setDel(mp[u][c].S,mp[u][c].getAns());}}curNode=u;while(curNode){Add(curNode,c,calDis(u,curNode));mp[curNode][c].S.insert(mp[curNode][c].getAns());int p=parent[curNode];if(p){mp[p][c].S.insert(*(mp[curNode][c].S.begin()));}curNode=p;}SS.insert(*mp[root][c].S.begin());
}void change(int u,int c)
{if(color[u]==c) return;del(u,color[u]);upd(u,c);color[u]=c;
}int main()
{n=myInt();for(int i=1;i<=n;i++) color[i]=myInt();clr(head,-1);for(int i=1;i<n;i++){int u=myInt();int v=myInt();int w=myInt();add(u,v,w);add(v,u,w);}init();clr(visit,0);root=DFS(1);for(it=mp[root].begin();it!=mp[root].end();it++){SS.insert(*(it->second.S.begin()));}int minDis=*SS.begin();printf("%d\n",minDis==INF?-1:minDis);m=myInt();while(m--){int x=myInt();int y=myInt();change(x,y);minDis=*SS.begin();printf("%d\n",minDis==INF?-1:minDis);}
}