func_code_string: #include <bits/stdc++.h>   const int MAXN = 100010, inf = 2147483233;   using namespace std;   inline int read() {     int x = 0, f = 1;     char ch = getchar();     while (!isdigit(ch)) {       if (ch ==  - ) f = -1;       ch = getchar();     }     while (isdigit(ch)) {       x = x * 10 + ch -  0 ;       ch = getchar();     }     return x * f;   }   int n, q, tot, nxt[MAXN << 1], to[MAXN << 1], fst[MAXN], cnt;   int fa[MAXN], hsh[MAXN], dep[MAXN], f[MAXN][25], HSH[MAXN], size[MAXN];   int mx[MAXN << 2][2], mn[MAXN << 2][2], mx1, mx2, mn1, mn2;   namespace hh {   using namespace std;   inline int read() {     int x = 0, f = 1;     char ch = getchar();     for (; !isdigit(ch); ch = getchar())       if (ch ==  - ) f = -f;     for (; isdigit(ch); ch = getchar()) x = 10 * x + ch -  0 ;     return x * f;   }   const int maxn = 500010;   int n, m, lastans;   int first[maxn], to[maxn << 1], nx[maxn << 1], cnt;   inline void add(int u, int v) {     to[++cnt] = v;     nx[cnt] = first[u];     first[u] = cnt;   }   inline void ins(int u, int v) {     add(u, v);     add(v, u);   }   namespace LCA {   int dep[maxn], bl[maxn], fa[maxn], size[maxn];   inline void dfs1(int x) {     size[x] = 1;     for (int i = first[x]; i; i = nx[i]) {       if (to[i] == fa[x]) continue;       fa[to[i]] = x;       dep[to[i]] = dep[x] + 1;       dfs1(to[i]);       size[x] += size[to[i]];     }   }   inline void dfs2(int x, int col) {     int k = 0;     bl[x] = col;     for (int i = first[x]; i; i = nx[i])       if (dep[to[i]] > dep[x] && size[to[i]] > size[k]) k = to[i];     if (!k) return;     dfs2(k, col);     for (int i = first[x]; i; i = nx[i])       if (dep[to[i]] > dep[x] && to[i] != k) dfs2(to[i], to[i]);   }   inline int lca(int x, int y) {     while (bl[x] != bl[y]) {       if (dep[bl[x]] < dep[bl[y]]) swap(x, y);       x = fa[bl[x]];     }     return dep[x] > dep[y] ? y : x;   }   }  // namespace LCA   namespace SEG {   int root[maxn][2], ls[maxn << 4], rs[maxn << 4], val[maxn << 4], size;   inline void Insert(int &x, int l, int r, int pos, int va) {     if (!x) x = ++size;     val[x] += va;     if (l == r) return;     int mid = (l + r) >> 1;     if (pos <= mid)       Insert(ls[x], l, mid, pos, va);     else       Insert(rs[x], mid + 1, r, pos, va);   }   inline int query(int x, int l, int r, int L, int R) {     if (!x) return 0;     if (L <= l && r <= R) return val[x];     int mid = (l + r) >> 1, ans = 0;     if (L <= mid) ans += query(ls[x], l, mid, L, R);     if (R > mid) ans += query(rs[x], mid + 1, r, L, R);     return ans;   }   }  // namespace SEG   inline int q_dis(int x, int y) {     return LCA::dep[x] + LCA::dep[y] - (LCA::dep[LCA::lca(x, y)] << 1);   }   int size[maxn], f[maxn], vis[maxn], d[maxn], v[maxn], son, root;   int nfa[maxn];   inline void solve(int rt, int type, int x, int fa) {     SEG::Insert(SEG::root[rt][type], 0, n, d[x], v[x]);     for (int i = first[x]; i; i = nx[i]) {       if (to[i] == fa || vis[to[i]]) continue;       d[to[i]] = d[x] + 1;       solve(rt, type, to[i], x);     }   }   inline void getroot(int x, int fa) {     size[x] = 1, f[x] = 0;     for (int i = first[x]; i; i = nx[i]) {       if (to[i] == fa || vis[to[i]]) continue;       getroot(to[i], x);       size[x] += size[to[i]];       f[x] = max(f[x], size[to[i]]);     }     f[x] = max(f[x], son - size[x]);     if (f[x] < f[root]) root = x;   }   inline void work(int x) {     vis[x] = 1;     d[x] = 0;     solve(x, 0, x, 0);     for (int i = first[x]; i; i = nx[i]) {       if (vis[to[i]]) continue;       son = size[to[i]];       root = 0;       d[to[i]] = 1;       getroot(to[i], 0);       solve(root, 1, to[i], x);       nfa[root] = x;       work(root);     }   }   inline int query(int x, int k) {     int ret = SEG::query(SEG::root[x][0], 0, n, 0, k);     for (int i = x; nfa[i]; i = nfa[i]) {       int du = q_dis(x, nfa[i]);       ret += SEG::query(SEG::root[nfa[i]][0], 0, n, 0, k - du);       ret -= SEG::query(SEG::root[i][1], 0, n, 0, k - du);     }     return ret;   }   inline void update(int x, int k) {     int delt = k - SEG::query(SEG::root[x][0], 0, n, 0, 0);     SEG::Insert(SEG::root[x][0], 0, n, 0, delt);     for (int i = x; nfa[i]; i = nfa[i]) {       int du = q_dis(x, nfa[i]);       SEG::Insert(SEG::root[nfa[i]][0], 0, n, du, delt);       SEG::Insert(SEG::root[i][1], 0, n, du, delt);     }   }   int main() {     n = read(), m = read();     for (int i = 1; i <= n; i++) v[i] = read();     for (int i = 2; i <= n; i++) {       int u = read(), v = read();       ins(u, v);     }     LCA::dfs1(1);     LCA::dfs2(1, 1);     f[0] = son = n;     getroot(1, 0);     work(root);     while (m--) {       int opt = read(), x = read() ^ lastans, y = read() ^ lastans;       if (opt)         update(x, y);       else         printf( %d n , lastans = query(x, y));     }   }   }  // namespace hh   void dfs(int x) {     hsh[x] = ++tot, HSH[tot] = x;     dep[x] = dep[f[x][0]] + 1;     for (int i = 1; i <= 23; i++) f[x][i] = f[f[x][i - 1]][i - 1];     for (int i = fst[x]; i; i = nxt[i]) dfs(to[i]);   }   int lca(int u, int v) {     if (dep[u] < dep[v]) swap(u, v);     int t = dep[u] - dep[v];     for (int i = 23; i >= 0; i--)       if ((1 << i) & t) u = f[u][i];     if (u == v) return u;     for (int i = 23; i >= 0; i--)       if (f[u][i] != f[v][i]) u = f[u][i], v = f[v][i];     return f[u][0];   }   void pushup(int x) {     mx[x][0] = max(mx[(x << 1)][0], mx[((x << 1) | 1)][0]);     mx[x][1] = max(min(mx[(x << 1)][0], mx[((x << 1) | 1)][0]),                    max(mx[(x << 1)][1], mx[((x << 1) | 1)][1]));     mn[x][0] = min(mn[(x << 1)][0], mn[((x << 1) | 1)][0]);     mn[x][1] = min(max(mn[(x << 1)][0], mn[((x << 1) | 1)][0]),                    min(mn[(x << 1)][1], mn[((x << 1) | 1)][1]));   }   void build(int x, int l, int r) {     if (l == r) {       mx[x][1] = 0;       mn[x][1] = inf;       mx[x][0] = mn[x][0] = hsh[l];       return;     }     int mid = l + r >> 1;     build((x << 1), l, mid);     build(((x << 1) | 1), mid + 1, r);     pushup(x);   }   void query(int x, int l, int r, int a, int b) {     if (a <= l && r <= b) {       if (mx[x][0] > mx1)         mx2 = mx1, mx1 = mx[x][0];       else if (mx[x][0] > mx2)         mx2 = mx[x][0];       if (mx[x][1] > mx2) mx2 = mx[x][1];       if (mn[x][0] < mn1)         mn2 = mn1, mn1 = mn[x][0];       else if (mn[x][0] < mn2)         mn2 = mn[x][0];       if (mn[x][1] < mn2) mn2 = mn[x][1];       return;     }     int mid = l + r >> 1;     if (a <= mid) query((x << 1), l, mid, a, b);     if (b > mid) query(((x << 1) | 1), mid + 1, r, a, b);   }   void init() {     cin >> n >> q;     for (int i = 2; i <= n; i++) {       f[i][0] = read();       to[++cnt] = i, nxt[cnt] = fst[f[i][0]], fst[f[i][0]] = cnt;     }   }   void work() {     dfs(1);     build(1, 1, n);   }   int a, b;   void gogo() {     mx1 = mx2 = 0;     mn1 = mn2 = inf;     query(1, 1, n, a, b);   }   void print() {     while (q--) {       int l1, l2;       cin >> a >> b;       gogo();       l1 = lca(HSH[mx1], HSH[mn2]);       l2 = lca(HSH[mx2], HSH[mn1]);       if (dep[l1] > dep[l2])         printf( %d %d n , HSH[mn1], dep[l1] - 1);       else         printf( %d %d n , HSH[mx1], dep[l2] - 1);     }   }   int main() {     init();     work();     print();   }   