谢谢各位大佬

#include<bits/stdc++.h>
using namespace std;
#define ll long long
int read() {
	int x = 0,f = 0;char ch = getchar();
	while(!isdigit(ch)) {if(ch == '-') f = 1;ch = getchar();}
	while(isdigit(ch)) {x = x * 10 + ch - '0';ch = getchar();}
	return f ? -x : x;
}
const int N = 1e6 + 100,inf = 0x3f3f3f3f;
struct Heap {
	priority_queue<int> s,t;
	void add(int x) {s.push(x);}
	void del(int x) {t.push(x);}
	void pre() {while(t.size() && s.top() == t.top()) s.pop(),t.pop();}
	int size() {return s.size() - t.size();}
	int top() {
		pre();if(s.size()) return s.top();
		else -inf;
	}
	int top2() {
		int x = top();del(x);int y = top();add(x);
		return y;
	}
	int ans() {
		if(size() >= 2) return top() + top2();
		else if(size() == 1) return max(top(),0);
		else return -inf;
	}
}A[N],B[N],Ans;
int n,col[N],cnt,Log[N];
struct Edge {int to,nxt,w;}e[N << 1];
int fa[N][21],dep[N],dis[N],head[N],ecnt; 
void addedge(int x,int y,int w) {e[++ecnt]=(Edge){y,head[x],w};head[x] = ecnt;}
int lca(int x,int y) {
	if(dep[x] < dep[y]) swap(x,y);
	int k = dep[x] - dep[y];for(int i = Log[k];~i;i--) {
		if((k >> i) & 1) x = fa[x][i];
	}if(x == y) return x;
	for(int i = Log[dep[x]];~i;i--) {
		if(fa[x][i] ^ fa[y][i]) x = fa[x][i],y = fa[y][i];
	}return fa[x][0];
}
int dist(int x,int y) {return dis[x] + dis[y] - 2 * dis[lca(x,y)];}
void Init(int x,int Fa,int Dep) {
	fa[x][0] = Fa;dep[x] = Dep;
	for(int i = 1;i <= Log[dep[x]];i++) fa[x][i] = fa[fa[x][i-1]][i-1];
	for(int i = head[x];i;i = e[i].nxt) {
		int y = e[i].to;if(y == Fa) continue;
		dis[y] = dis[x] + e[i].w;Init(y,x,Dep+1);
	}
}
int rt,maxs[N],size[N],vis[N],dfa[N];
void getrt(int x,int Fa,int tots) {
	size[x] = 1;maxs[x] = 0;
	for(int i = head[x];i;i = e[i].nxt) {
		int y = e[i].to;if(vis[y] || y == Fa) continue;
		getrt(y,x,tots);size[x] += size[y];
		maxs[x] = max(maxs[x],size[y]);
	}maxs[x] = max(tots - size[x],maxs[x]);
	if(maxs[rt] > maxs[x]) rt = x;
}
void rebuild(int x,int Fa,int tots) {
	vis[x] = 1;dfa[x] = Fa;
	for(int i = head[x];i;i = e[i].nxt) {
		int y = e[i].to;if(vis[y]) continue;
		maxs[rt = 0] = inf;
		int Tot = (size[x] < size[y]) ? tots - size[y] : size[y]; 
		getrt(y,x,Tot);rebuild(rt,x,Tot);
	}
}
void Add(int x) {if(A[x].size() >= 2) Ans.add(A[x].ans());/*cout << A[x].ans() << endl;*/} 
void Del(int x) {if(A[x].size() >= 2) Ans.del(A[x].ans());/*cout << A[x].ans() << endl;*/}
void update(int x) {
	!col[x] ? --cnt : ++cnt;col[x] = 1 - col[x];
	if(col[x]) {Del(x);A[x].del(0);Add(x);}
	else {Del(x);A[x].add(0);Add(x);}
	for(int now = x;dfa[now];now = dfa[now]) {
		int F = dfa[now],d = dist(x,F);
//		cout << d << " " << " u :: " << x << " v ::" << F << endl;
		if(col[x]) {
			Del(F);
			if(B[now].size()) A[F].del(B[now].top());
			if(B[now].size()) B[now].del(d);
			if(B[now].size()) A[F].add(B[now].top());
			Add(F);
		}
		else {
			Del(F);
			if(B[now].size()) A[F].del(B[now].top());
			B[now].add(d);
			A[F].add(B[now].top());
			Add(F);
		}
	}
}
int query() {
	if(cnt >= 2) return max(Ans.top(),0);
	else if(cnt == 1) return 0;
	else return -inf;
}
int main() {
	n = read();
	for(int i = 2;i <= n;i++) Log[i] = Log[i >> 1] + 1;
	for(int i = 1,u,v,w;i < n;i++) {
		u = read();v = read();w = read();
		addedge(u,v,w);addedge(v,u,w);
	}Init(1,0,1);maxs[rt = 0] = inf;getrt(1,0,n);
	rebuild(rt,0,n);int Q = read();cnt = 0;
//	for(int i = 1;i <= n;i++) {
//		cout << i << " dfa[i]:: " << dfa[i] << endl;
//	}
	for(int i = 1;i <= n;i++) {
		col[i] = 1;update(i);
	}
	while(Q--) {
		char ch[10];scanf("%s",ch + 1);
		if(ch[1] == 'A') {
			int res = query();
			if(res <= -inf) printf("They have disappeared.\n");
			else printf("%d\n",res);
		}
		else {int x = read();update(x);}
	}
	
}