URAL 1553. Caves and tunnels tree chain split

A tree each starting point right-click value is 0

2 operating mode 1. First I right-click value Add x 2. Begging u to V on this road upper right value

Tree-based interlocking division title

#include <cstdio> #include <cstring> #include <algorithm>using namespace std;const int maxn = 100010; struct Edge{int V, next;} E[maxn*2];int FIRST[MAXN], cnt;void addedge (int u, int v) {e[cnt].v = V;e[cnt].next = First[u];first[u] = CNT++;E[CNT].V = U;e[cnt].next = first[v];first[v] = cnt++;} int TOP[MAXN], SZ[MAXN], SON[MAXN], F[MAXN], Dep[maxn];int N, Id[maxn], RANK[MAXN], tid;void init () {memset (First,-1, size of (first)); cnt = 0;memset (son,-1, sizeof (son)); tid = 0;} void dfs1 (int u, int fa, int d) {Sz[u] = 1;f[u] = Fa;dep[u] = d;for (int i = first[u]; i = 1; i = e[i].next) {int v = e[i]. V;if (v = = FA) continue;dfs1 (V, U, d+1); Sz[u] + = sz[v];if (Son[u] = = 1 | | sz[son[u]] < SZ[V]) son[u] = V;}} void dfs2 (int u, int tp) {Top[u] = Tp;id[u] = ++tid;rank[tid] = u;if (Son[u] = =-1) return;dfs2 (Son[u], TP); for (int i = First [u]; I! =-1; i = e[i].next) {int v = e[i].v;if (v = f[u] && son[u]! = v) dfs2 (V, v);}} int a[maxn<<2];void pushup (int rt) {A[rt] = max (a[rt<<1], a[rt<<1|1]);}  void build (int l, int r, int rt) {A[rt] = 0;if (L = = r) Return;int m = (L + R) >> 1;build (L, M, rt<<1); Build (M+1, R, rt<<1|1);} int query (int x, int y, int l, int r, int rt) {if (x = = L && y = = r) {return A[RT];} int m = (L + R) >> 1;if (y <= m) return query (x, Y, L, M, rt<<1), else if (x > M) return query (x, Y, m+1, R, rt<<1|1); Else{return max (query (x, M, L, M, rt<<1), query (m+1, y, m+1, R, Rt<<1|1));}} void update (int x, int l, int r, int rt, int d) {if (L = = r) {A[rt] + = D;return;} int m = (L + R) >> 1;if (x <= m) update (x, L, M, rt<<1, D); Elseupdate (x, m+1, R, Rt<<1|1, D);p Ushup (RT) ;} int change (int u, int v) {int ans = 0;while (top[u]! = Top[v]) {if (Dep[top[u]] < DEP[TOP[V]) swap (U, v); ans = max (ans, que Ry (Id[top[u]], id[u], 1, N, 1)); u = F[top[u]];} if (Dep[u] > Dep[v]) Swap (U, v); ans = max (ans, query (Id[u], id[v], 1, N, 1)); return ans; int main () {while (scanf ("%d", &n)! = EOF) {init (); for (int i = 1; I < n; i++) {int u, v;scanf ("%d%d", &u, &v); Addedge (U, v);} DFS1 (1, 0, 0);d FS2 (1, 1); Build (1, N, 1), int q;scanf ("%d", &q), while (q--) {char s[10];int u, v;scanf ("%s%d%d", S, &amp ; u, &v), if (s[0] = = ' G ') {printf ("%d\n", Change (U, v));} Else{update (Id[u], 1, N, 1, v);}} return 0;}

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URAL 1553. Caves and tunnels tree chain split