# 【BZOJ 3531】【SDOI 2014】旅行

#include<cstdio>
#include<cstring>
#include<algorithm>
#define N 100003
using namespace std;
inline int getint() {int k = 0, fh = 1; char c = getchar(); for(; c < '0' || c > '9'; c = getchar()) if (c == '-') fh = -1; for(; c >= '0' && c <= '9'; c = getchar()) k = k * 10 + c - '0'; return k * fh;}
struct Tree {
int l, r, ma, sm;
} T[4000010];
struct G {
int nxt, to;
} E[N << 1];
int root[N], point[N], cnt = 0, n, q, W[N], C[N], sz[N], son[N], up[N];
int deep[N], fa[N], watch[N];
inline void ins(int x, int y) {E[++cnt].nxt = point[x]; E[cnt].to = y; point[x] = cnt;}
inline void _(int x) {
sz[x] = 1;
for(int tmp = point[x]; tmp; tmp = E[tmp].nxt) {
int v = E[tmp].to;
if (v == fa[x]) continue;
fa[v] = x;
deep[v] = deep[x] + 1;
_(v);
if (sz[v] > sz[son[x]])
son[x] = v;
sz[x] += sz[v];
}
}
inline void __(int x) {
watch[x] = ++cnt;
if (!son[x]) return;
up[son[x]] = up[x];
__(son[x]);
for(int tmp =point[x]; tmp; tmp = E[tmp].nxt) {
int v = E[tmp].to;
if (v == fa[x] || v == son[x]) continue;
up[v] = v;
__(v);
}
}

inline void pushup(int pos) {
T[pos].sm = T[T[pos].l].sm + T[T[pos].r].sm;
T[pos].ma = max(T[T[pos].l].ma, T[T[pos].r].ma);
}
inline void update(int &pos, int l, int r, int to, int num) {
if (pos == 0) pos = ++cnt;
if (l == r) {T[pos].ma = T[pos].sm = num; return;}
int mid = (l + r) >> 1;
if (to <= mid) update(T[pos].l, l, mid, to, num);
else update(T[pos].r, mid + 1, r, to, num);
pushup(pos);
}
inline int Qsum(int pos, int L, int R, int l, int r) {
if (L <= l && r <= R) return T[pos].sm;
int mid = (l + r) >> 1, s = 0;
if (L <= mid) s += Qsum(T[pos].l, L, R, l, mid);
if (R > mid) s += Qsum(T[pos].r, L, R, mid + 1, r);
return s;
}
inline int Qmax(int pos, int L, int R, int l, int r) {
if (L <= l && r <= R) return T[pos].ma;
int mid = (l + r) >> 1, s = 0;
if (L <= mid) s = Qmax(T[pos].l, L, R, l, mid);
if (R > mid) s = max(s, Qmax(T[pos].r, L, R, mid + 1, r));
return s;
}

inline int Max(int CC, int x, int y) {
int ans = 0;
while (up[x] != up[y]) {
if (deep[up[x]] < deep[up[y]]) swap(x, y);
ans = max(ans, Qmax(root[CC], watch[up[x]], watch[x], 1, n));
x = fa[up[x]];
}
if (deep[x] > deep[y]) swap(x, y);
ans = max(ans, Qmax(root[CC], watch[x], watch[y], 1, n));
return ans;
}
inline int Sum(int CC, int x, int y) {
int ans = 0;
while (up[x] != up[y]) {
if (deep[up[x]] < deep[up[y]]) swap(x, y);
ans += Qsum(root[CC], watch[up[x]], watch[x], 1, n);
x = fa[up[x]];
}
if (deep[x] > deep[y]) swap(x, y);
ans += Qsum(root[CC], watch[x], watch[y], 1, n);
return ans;
}

int main() {
for(int i = 1; i <= n; ++i)
int u, v;
for(int i = 1; i < n; ++i) {
ins(u, v); ins(v, u);
}
_(1);
up[1] = 1;
cnt = 0;
__(1);
cnt = 0;
for(int i = 1; i <= n; ++i)
update(root[C[i]], 1, n, watch[i], W[i]);
char c; int x, y;
for(int i = 1; i <= q; ++i) {
for(c = getchar(); c < 'A' || c > 'Z'; c = getchar());
if (c == 'C') {
if (c == 'C') {
update(root[C[x]], 1, n, watch[x], 0);
C[x] = y;
update(root[C[x]], 1, n, watch[x], W[x]);
} else {
update(root[C[x]], 1, n, watch[x], y);
W[x] = y;
}
} else {
if (c == 'S')
printf("%d\n", Sum(C[x], x, y));
else
printf("%d\n", Max(C[x], x, y));
}
}
return 0;
}

hhhhhhhhhhhhhhhhhh调出来真的不容易啊，树链剖分怎么比$LCT$都难写！！！

$Try$ $Everything$

NOI 2017 Bless All
posted @ 2016-04-04 15:08  abclzr  阅读(151)  评论(0编辑  收藏  举报