#include<bits/stdc++.h>
using namespace std;
int n,ttt,siz[100005],son[100005],fa[100005],top[100005],num[100005],id[100005],father[100005][17],idx,qlog[100005],deep[100005],g[100005],head[100005],tot;
struct node
{
	int v,w,nxt;
}edge[200005];
inline void add(int u,int v,int w)
{
	edge[++tot]={v,w,head[u]};
	head[u]=tot;
}
inline void read(int &a)
{
	a=0;register char c;
	while((c=getchar())<48);
	do a=(a<<3)+(a<<1)+(c^48);
	while((c=getchar())>47);
}
inline void write(int x)
{
	if(x<=0)return;
	write(x/10);
	putchar(x%10+'0');
}
inline void read_string(register string &a)
{
	a="";register char c;
	while((c=getchar())<'A'||c>'Z');
	do a+=c;
	while((c=getchar())>='A'&&c<='Z');
}
struct tree
{
	int sum[500005];
	inline void pushup(int num)
	{
		sum[num]=max(sum[num<<1],sum[num<<1|1]);
	}
	inline void build(int l,int r,int num)
	{
		if(l==r)
		{
			sum[num]=0;
			return;
		}
		int mid=(l+r)>>1;
		build(l,mid,num<<1),build(mid+1,r,num<<1|1);
		pushup(num);
	}
	inline void update(int pos,int x,int l,int r,int num)
	{
		if(l==r&&l==pos) 
		{
			sum[num]=x;
			return;
		}
		int mid=(l+r)>>1;
		if(pos<=mid)update(pos,x,l,mid,num<<1);
		if(pos>mid)update(pos,x,mid+1,r,num<<1|1);
		pushup(num);
	}
	inline int query(int L,int R,int l,int r,int num)
	{
		if(L<=l&&r<=R)return sum[num];
		int mid=(l+r)>>1;
		int res=0;
		if(L<=mid)res=max(res,query(L,R,l,mid,num<<1));
		if(R>mid)res=max(res,query(L,R,mid+1,r,num<<1|1));
		return res;
	}
}tr;
inline void dfs(int x,int fat)
{
	int maxn=0;
	siz[x]=1;
	father[x][0]=fat;
	deep[x]=deep[fat]+1;
	for(int i=1;i<=qlog[deep[x]];i++)father[x][i]=father[father[x][i-1]][i-1];
	for(int i=head[x];i;i=edge[i].nxt)
	{
		if(edge[i].v==fat)continue;
		dfs(edge[i].v,x);
		siz[x]+=siz[edge[i].v];
		if(siz[edge[i].v]>maxn)
		{
			maxn=siz[edge[i].v];
			son[x]=i;
		}
	}
}
inline int lca(int x,int y)
{
	if(deep[x]<deep[y])swap(x,y);
	while(deep[x]>deep[y])x=father[x][qlog[deep[x]-deep[y]]-1];
	if(x==y)return x;
	for(int i=qlog[deep[x]]-1;i>=0;i--)
		if(father[x][i]!=father[y][i])
		{
			x=father[x][i];
			y=father[y][i];
		}
	return father[x][0];
}
inline void dfs2(int x,int fat,int topx,int w)
{
	id[x]=++idx;
	top[idx]=id[topx];
	num[idx]=x;
	fa[idx]=id[fat];
	g[w/2+1]=idx;
	tr.update(idx,edge[w].w,1,n,1);
//	cout<<x<<"dfxjk;dfg"<<son[x]<<endl;
//	cout<<"top:"<<x<<" "<<top[x]<<" "<<topx<<endl;
	if(son[x])dfs2(edge[son[x]].v,x,topx,son[x]);
	for(int i=head[x];i;i=edge[i].nxt)
	{
		if(edge[i].v==fat||i==son[x])continue;
		dfs2(edge[i].v,x,edge[i].v,i);
	}
}
inline int query(int x,int y)
{
	int f=id[lca(x,y)];
	int res=0;
	x=id[x];
	while(x>0)
	{
	//	cout<<x<<" "<<top[x]<<" "<<tr.query(1,2,1,n,1)<<endl;
		bool flag=0;
		int end=top[x];
		if(top[x]<=f&&f<=x)
		{
			end=f+1;
			flag=1;
		}
		res=max(res,tr.query(end,x,1,n,1));
		if(flag)break;
	//	cout<<"jump:"<<x<<" "<<top[x]<<endl;
		x=fa[top[x]];
	}
	y=id[y];
	while(y>0)
	{
	//	cout<<x<<" "<<top[x]<<" "<<tr.query(1,2,1,n,1)<<endl;
		bool flag=0;
		int end=top[y];
		if(top[y]<=f&&f<=y)
		{
			end=f+1;
			flag=1;
		}
		res=max(res,tr.query(end,y,1,n,1));
		if(flag)break;
	//	cout<<"jump:"<<x<<" "<<top[x]<<endl;
		y=fa[top[y]];
	}
	return res;
}
signed main()
{
//	freopen("data.in","r",stdin);
//	freopen("code.out","w",stdout); 
	read(ttt);
	for(int i=1;i<=100000;i++)qlog[i]=qlog[i-1]+(1<<qlog[i-1]==i);
	while(ttt--)
	{
		idx=0;
		read(n);
		tr.build(1,n,1);
		memset(son,0,sizeof son);
		memset(head,0,sizeof head);
		tot=0;
		for(int i=1;i<n;i++)
		{
			int u,v,w;
			read(u),read(v),read(w);
			add(u,v,w);
			add(v,u,w); 
		}
		dfs(1,0);
		dfs2(1,0,1,0);
		string op;
		while(1)
		{
			read_string(op);
			if(op=="DONE")break;
			if(op=="CHANGE")
			{
				int x,v;
				read(x),read(v);
				tr.update(g[x],v,1,n,1);
			}
			if(op=="QUERY")
			{
				int x,y;
				read(x),read(y);
				int res=query(x,y);
				if(res==0)putchar('0');
				else write(res); 
				putchar('\n');
			}
		}
	}
}