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#include <bits/stdc++.h>
using namespace std;
template <typename T> inline void read(T &a){
T w=1; a=0;
char ch=getchar();
for(;ch < '0' || ch > '9';ch=getchar()) if(ch == '-') w=-1;
for(;ch>='0'&&ch<='9';ch=getchar()) a=(a<<3)+(a<<1)+(ch^48);
a*=w;
}
template <typename T> inline void ckmax(T &a, T b){a = a > b ? a : b;}
template <typename T> inline void ckmin(T &a, T b){a = a < b ? a : b;}
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define vi vector<int>
#define Debug(x) cout << #x << " = " << x << endl
#define For(i,l,r) for (int i = l; i <= r; ++i)
#define foR(i,l,r) for (int i = l; i >= r; --i)
#define int long long
const int N = 1e5 + 10;
struct edge {
int to, nxt, dis;
} e[N << 1];
int head[N], cnt;
inline void add (int u, int v, int w) {
e[++cnt].to = v; e[cnt].nxt = head[u]; e[cnt].dis = w; head[u] = cnt;
}
int dep[N], dis[N];
int dp[N][32], val[N][32];
int dfn[N], dfntot, rnk[N];
void Init (int u, int fa) {
dep[u] = dep[fa] + 1;
dp[u][0] = fa;
dfn[u] = ++dfntot;
rnk[dfntot] = u;
for (int i = 1; (1 << i) <= dep[u]; ++i)
dp[u][i] = dp[dp[u][i - 1]][i - 1];
for (int i = head[u]; i; i = e[i].nxt) {
int v = e[i].to;
if (v == fa) continue;
dis[v] = dis[u] + e[i].dis;
Init(v, u);
}
}
int LCA (int x, int y) {
if (dep[x] < dep[y]) swap(x, y);
foR (i, 22, 0)
if (dep[x] - (1 << i) >= dep[y]) x = dp[x][i];
if (x == y) return x;
foR (i, 22, 0)
if (dp[x][i] != dp[y][i]) x = dp[x][i], y = dp[y][i];
return dp[x][0];
}
int Dis (int x, int y) {
int lca = LCA(x, y);
return dis[x] + dis[y] - 2 * dis[lca];
}
set <int> mck;
int Ans;
void ins (int x) {
mck.insert (dfn[x]);
if (mck.size() <= 1) return ;
auto it = mck.lower_bound(dfn[x]), en = mck.end(); en--;
if (it == mck.begin()) {
auto fo = it; fo++;
Ans -= Dis(rnk[*fo], rnk[*en]);
Ans += Dis(x, rnk[*fo]);
Ans += Dis(x, rnk[*en]);
}
else if (it == en) {
auto fo = it; fo--;
Ans -= Dis(rnk[*mck.begin()], rnk[*fo]);
Ans += Dis(rnk[*mck.begin()],rnk[*en]);
Ans += Dis(rnk[*fo], rnk[*en]);
}
else {
auto la = it, nx = it; la--, nx++;
Ans -= Dis(rnk[*la], rnk[*nx]);
Ans += Dis(rnk[*la], x);
Ans += Dis(rnk[*nx], x);
}
}
void era (int x) {
if (mck.size() <= 1) {mck.erase(dfn[x]); return ;}
auto it = mck.lower_bound(dfn[x]), en = mck.end(); en--;
if (it == mck.begin()) {
auto fo = it; fo++;
Ans += Dis(rnk[*fo], rnk[*en]);
Ans -= Dis(x, rnk[*fo]);
Ans -= Dis(x, rnk[*en]);
}
else if (it == en) {
auto fo = it; fo--;
Ans += Dis(rnk[*mck.begin()], rnk[*fo]);
Ans -= Dis(rnk[*mck.begin()],rnk[*en]);
Ans -= Dis(rnk[*fo], rnk[*en]);
}
else {
auto la = it, nx = it; la--, nx++;
Ans += Dis(rnk[*la], rnk[*nx]);
Ans -= Dis(rnk[*la], x);
Ans -= Dis(rnk[*nx], x);
}
mck.erase(dfn[x]);
}
signed main() {
int n; read(n);
For (i, 1, n - 1) {
int u, v, w; read(u); read(v); read(w);
add(u, v, w), add(v, u, w);
}
Init(1, 0);
puts("");
int m; read(m);
while (m--) {
char opt[3]; int x;
scanf ("%s", opt);
if (opt[0] == '+') {
read(x); ins(x);
}
if (opt[0] == '-') {
read(x); era(x);
}
if (opt[0] == '?')
printf ("%lld\n", Ans / 2ll);
}
}
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