# 6, 7, 8 三个测试点 RE

#include <bits/stdc++.h>
using namespace std;

const int maxn = 3e5, logn = 18;
int n, m, dep[maxn + 3], mx[maxn + 3], ch[maxn + 3], fa[maxn + 3][logn + 3];
int top[maxn + 3], bot[maxn + 3], len[maxn + 3], ans, lg[maxn + 3];
vector<int> G[maxn + 3], S[maxn + 3];

void dfs(int u, int pa = 0) {
for (int i = 1; (fa[u][i] = fa[fa[u][i - 1]][i - 1]); i++);
for (int i = 0, v; i < G[u].size(); i++) {
v = G[u][i];
if (v == pa) continue;
fa[v][0] = u;
dep[v] = dep[u] + 1;
dfs(v, u);
if (mx[v] + 1 > mx[u]) {
mx[u] = mx[v] + 1, ch[u] = v;
}
}
}

void solve(int u, int pa = 0, int t = 1) {
top[u] = t;
for (int i = 0, v; i < G[u].size(); i++) {
v = G[u][i];
if (v == pa || v == ch[u]) continue;
solve(v, u, v);
}
if (ch[u]) {
len[top[u]]++;
solve(ch[u], u, t);
} else {
bot[top[u]] = u;
}
S[top[u]].push_back(u);
if (u == t) {
for (int i = 1, x = u; i <= len[u]; i++) {
S[u].push_back(x = fa[x][0]);
}
}
}

int query(int x, int k) {
if (k == 0) {
return x;
} else if (k > dep[x]) {
return 0;
}
int t = lg[k];
x = fa[x][t], k -= 1 << t;
return S[top[x]][dep[bot[top[x]]] - dep[x] + k];
}

int main() {
scanf("%d", &n);
for (int i = 2; i <= n; i++) {
lg[i] = lg[i >> 1] + 1;
}
for (int i = 1, u, v; i < n; i++) {
scanf("%d %d", &u, &v);
G[u].push_back(v), G[v].push_back(u);
}
dfs(1);
solve(1);
scanf("%d", &m);
for (int x, k; m --> 0; ) {
scanf("%d %d", &x, &k);
x ^= ans, k ^= ans;
printf("%d\n", ans = query(x, k));
}
return 0;
}

8

2181

184

8%