【BZOJ3730】【动态点分治模板题】震波

Description

在一片土地上有N个城市,通过N-1条无向边互相连接,形成一棵树的结构,相邻两个城市的距离为1,其中第i个城市的价值为value[i]。
不幸的是,这片土地常常发生地震,并且随着时代的发展,城市的价值也往往会发生变动。
接下来你需要在线处理M次操作:
0 x k 表示发生了一次地震,震中城市为x,影响范围为k,所有与x距离不超过k的城市都将受到影响,该次地震造成的经济损失为所有受影响城市的价值和。
1 x y 表示第x个城市的价值变成了y。
为了体现程序的在线性,操作中的x、y、k都需要异或你程序上一次的输出来解密,如果之前没有输出,则默认上一次的输出为0。


Solution

动态点分治模板题。
其实不是很难,在普通点分治的基础上,记录了每次点分治的根节点,形成了一棵点分树。对于每个节点建两棵线段树,像普通点分治一样容斥一下就好了。

但这题是真TM卡常数,卡了一晚上,卡了线段树的上界才过QAQ

DYX说用树状数组就不用卡常了orzorz


Code

/************************************************
 * Au: Hany01
 * Date: Jul 7th, 2018
 * Prob: BZOJ3730
 * Email: [email protected]
 * Inst: Yali High School
************************************************/

#include<bits/stdc++.h>

using namespace std;

typedef long long LL;
typedef pair<int, int> PII;
#define File(a) freopen(a".in", "r", stdin), freopen(a".out", "w", stdout)
#define rep(i, j) for (register int i = 0, i##_end_ = (j); i < i##_end_; ++ i)
#define For(i, j, k) for (register int i = (j), i##_end_ = (k); i <= i##_end_; ++ i)
#define Fordown(i, j, k) for (register int i = (j), i##_end_ = (k); i >= i##_end_; -- i)
#define Set(a, b) memset(a, b, sizeof(a))
#define Cpy(a, b) memcpy(a, b, sizeof(a))
#define x first
#define y second
#define pb(a) push_back(a)
#define mp(a, b) make_pair(a, b)
#define ALL(a) (a).begin(), (a).end()
#define INF (0x3f3f3f3f)
#define INF1 (2139062143)
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define y1 wozenmezhemecaia

inline int read()
{
    static int _, __; static char c_;
    for (_ = 0, __ = 1, c_ = getchar(); c_ < '0' || c_ > '9'; c_ = getchar()) if (c_ == '-') __ = -1;
    for ( ; c_ >= '0' && c_ <= '9'; c_ = getchar()) _ = (_ << 1) + (_ << 3) + (c_ ^ 48);
    return _ * __;
}

const int maxn = 100001;

int n, beg[maxn], v[maxn << 1], nex[maxn << 1], e, Fa[maxn], maxch[maxn], sz[maxn], vis[maxn], dep[maxn], ns, rt, val[maxn], Rt[maxn << 1], tot, ST[21][maxn * 3], Log[maxn * 3], pos[maxn], SZ[maxn];

struct SegmentTreeNode { int lc, rc, val; } tr[maxn * 40];

void init(int u, int pa = 0) {
    ST[0][pos[u] = ++ tot] = u;
    for (register int i = beg[u]; i; i = nex[i]) if (v[i] != pa)
        dep[v[i]] = dep[u] + 1, init(v[i], u), ST[0][++ tot] = u;
}

inline int LCA(int u, int v) {
    static int l, r, x, y, t;
    l = pos[u], r = pos[v];
    if (l > r) swap(l, r);
    return dep[x = ST[t = Log[r - l + 1]][l]] < dep[y = ST[t][r - (1 << t) + 1]] ? x : y;
}

inline int dist(int u, int v) { return dep[u] + dep[v] - (dep[LCA(u, v)] << 1); }

void getrt(int u, int pa = 0) {
    sz[u] = 1, maxch[u] = 0;
    for (register int i = beg[u]; i; i = nex[i]) if (v[i] != pa && !vis[v[i]]) {
        getrt(v[i], u), sz[u] += sz[v[i]];
        if (maxch[u] < sz[v[i]]) maxch[u] = sz[v[i]];
    }
    if (maxch[u] < ns - sz[u]) maxch[u] = ns - sz[u];
    if (maxch[u] < maxch[rt]) rt = u;
}

void gettree(int u, int pa = 0) {
    vis[u] = 1, Fa[u] = pa, SZ[u] = 1;
    for (register int i = beg[u], prens = ns, t; i; i = nex[i]) if (!vis[v[i]])
        ns = sz[u] < sz[v[i]] ? prens - sz[u] : sz[v[i]], rt = 0, getrt(v[i]), t = rt, gettree(rt, u), SZ[u] += SZ[t];
}

#define mid ((l + r) >> 1)
void update(int &t, int l, int r, int x, int dt) {
    if (!t) t = ++ tot;
    tr[t].val += dt;
    if (l == r) return;
    if (x <= mid) update(tr[t].lc, l, mid, x, dt);
    else update(tr[t].rc, mid + 1, r, x, dt);
}
#undef mid
int query(int t, int l, int r, int x, int y) {
    if (!t) return 0;
    if (x <= l && r <= y) return tr[t].val;
    register int mid = (l + r) >> 1;
    if (y <= mid) return query(tr[t].lc, l, mid, x, y);
    if (x >  mid) return query(tr[t].rc, mid + 1, r, x, y);
    return query(tr[t].lc, l, mid, x, y) + query(tr[t].rc, mid + 1, r, x, y);
}

inline void writeln(int x)
{
    static int num[11], cnt;
    for (cnt = 0; x; x /= 10) num[++ cnt] = x % 10;
    if (!cnt) putchar(48);
    else while (cnt) putchar(num[cnt --] ^ 48);
    putchar('\n');
}

int main()
{
#ifndef ONLINE_JUDGE
    File("bzoj3730");
#endif

    static int uu, vv, op, m, lastans;

    n = read(), m = read();
    for (register int i = 1; i <= n; ++ i) val[i] = read();
    for (register int i = 2; i <= n; ++ i)
        uu = read(), vv = read(), v[++ e] = vv, nex[e] = beg[uu], beg[uu] = e, v[++ e] = uu, nex[e] = beg[vv], beg[vv] = e;

    init(1);
    For(i, 2, tot) Log[i] = Log[i >> 1] + 1;
    For(j, 1, Log[tot]) For(i, 1, tot - (1 << j) + 1)
        ST[j][i] = dep[uu = ST[j - 1][i]] > dep[vv = ST[j - 1][i + (1 << (j - 1))]] ? vv : uu;
    maxch[0] = INF, ns = n, rt = 0, getrt(1), gettree(rt);

    For(i, 1, n) {
        register int dt = val[i];
        update(Rt[i], 0, SZ[i] - 1, 0, dt);
        for (register int v = i, t; Fa[v]; v = Fa[v])
            update(Rt[Fa[v]], 0, SZ[Fa[v]] - 1, t = dep[i] + dep[Fa[v]] - (dep[LCA(i, Fa[v])] << 1), dt), update(Rt[v + n], 0, SZ[Fa[v]] - 1, t, dt);
    }
    while (m --) {
        op = read(), uu = read() ^ lastans, vv = read() ^ lastans;
        if (op) {
            register int dt = vv - val[uu];
            update(Rt[uu], 0, SZ[uu] - 1, 0, dt);
            for (register int v = uu, t; Fa[v]; v = Fa[v])
                update(Rt[Fa[v]], 0, SZ[Fa[v]] - 1, t = dep[uu] + dep[Fa[v]] - (dep[LCA(uu, Fa[v])] << 1), dt), update(Rt[v + n], 0, SZ[Fa[v]] - 1, t, dt);
            val[uu] = vv;
        }
        else {
            lastans = query(Rt[uu], 0, SZ[uu] - 1, 0, vv);
            for (register int v = uu, t; Fa[v]; v = Fa[v])
                lastans += query(Rt[Fa[v]], 0, SZ[Fa[v]] - 1, 0, vv - (t = dep[uu] + dep[Fa[v]] - (dep[LCA(uu, Fa[v])] << 1))), lastans -= query(Rt[v + n], 0, SZ[Fa[v]] - 1, 0, vv - t);
            writeln(lastans);
        }
    }

    return 0;
}
//明朝寒食了,又是一年春。
//    -- 顾太清《临江仙·清明前一日种海棠》

猜你喜欢

转载自blog.csdn.net/hhaannyyii/article/details/80968366