[Luogu] 1600

https://www.luogu.org/problemnew/show/P1600

nlogn竟然T了

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <queue>
#include <map>
#include <vector>

using namespace std;
const int N = 600001;
const int oo = 99999999;

#define lson jd << 1
#define rson jd << 1 | 1 

#define yxy getchar() 
#define one_ n <= 993 
#define two_ n == 99994
#define three_ n == 99995

int head[N], pre[N], dis[N], tim[N], Answer[N], Askl[N], Askr[N];
bool vis[N];
int n, m, now = 1;
struct Node {int u, v, w, nxt;}G[N];
queue <int> Q;
vector <int> Vt[N];
int bef[N], top[N], deep[N], size[N], fa[N], son[N], tree[N], spjs;
int L[N << 2], R[N << 2], W[N << 2], F[N << 2];
int ans;

inline int read() {
    int x = 0; char c = yxy;
    while(c < '0' || c > '9') c = yxy;
    while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = yxy;
    return x;
}

inline void add(int u, int v) {G[now].v = v;G[now].nxt = head[u]; head[u] = now ++;}

inline void spfa(int start,int endd) {
    for(int i = 1; i <= n; i ++) dis[i] = oo, vis[i] = 0;
    dis[start] = 0;
    Q.push(start);
    while(!Q.empty()) {
        int topp = Q.front(); Q.pop();
        vis[topp] = 0;
        for(int i = head[topp]; ~ i; i = G[i].nxt) {
            if(dis[G[i].v] > dis[topp] + 1) {
                dis[G[i].v] = dis[topp] + 1;
                pre[G[i].v] = topp;
                if(!vis[G[i].v]) {vis[G[i].v] = 1; Q.push(G[i].v);}
            }
        }
    }
}

void calc(int start, int endd, int diss) {
    int js = -1; pre[start] = 0;
    while(endd) {
        js ++;
        if(tim[endd] == diss - js) Answer[endd] ++;
        endd = pre[endd];
    }
}

void work_1() {
    for(int i = 1; i <= m; i ++) {
        spfa(Askl[i], Askr[i]);
        calc(Askl[i], Askr[i], dis[Askr[i]]);
    }
}

void work_2() {
    for(int i = 1; i <= m; i ++) Vt[Askl[i]].push_back(Askr[i]);
    for(int i = 1; i <= n; i ++) {
        int L_ = i - tim[i], R_ = i + tim[i];
        int siz_ = Vt[L_].size();
        if(L_ > 0)
            for(int j = 0; j < siz_; j ++) 
                if(Vt[L_][j] >= i) Answer[i] ++;
        siz_ = Vt[R_].size();
        if(R_ <= n)
            for(int j = 0; j < siz_; j ++)
                if(Vt[R_][j] <= i) Answer[i] ++;
    }
}

void Dfs_son(int u, int f_, int dep) {
    printf("%d %d\n", u, f_);
    fa[u] = f_;
    deep[u] = dep;
    size[u] = 1;
    for(int i = head[u]; ~ i; i = G[i].nxt) {
        int v = G[i].v;
        if(v != f_) {
            Dfs_son(v, u, dep + 1);
            if(size[v] > size[son[u]]) son[u] = v;
        }
    }
}

void Dfs_un(int u, int tp){
    top[u] = tp;
    tree[u] = ++ spjs;
    bef[spjs] = u;
    if(!son[u]) return ;
    Dfs_un(son[u], tp);
    for(int i = head[u]; ~ i; i = G[i].nxt) {
        int v = G[i].v;
        if(v != fa[u] && v != son[u]) Dfs_un(v, v);
    }
}

void Sec_G(int l, int r, int jd, int x, int y) {
    if(x <= l && r <= y) {
        F[jd] ++; W[jd] += (r - l + 1); return ;
    }
    int mid = (l + r) >> 1;
    if(x <= mid) Sec_G(l, mid, lson, x, y);
    if(y > mid)  Sec_G(mid + 1, r, rson, x, y);
    W[jd] = W[lson] + W[rson];
}

void down(int jd) {
    F[lson] += F[jd]; F[rson] += F[jd];
    W[lson] += (R[lson] - L[lson] + 1) * F[jd];
    W[rson] += (R[rson] - L[rson] + 1) * F[jd];
    F[jd] = 0;
}

inline void Sec_G_imp(int x, int y) {
    int tp1 = deep[x], tp2 = deep[y];
    while(tp1 != tp2) {
        if(deep[tp1] < deep[tp2]) swap(x, y), swap(tp1, tp2);
        Sec_G(1, n, 1, tree[tp1], tree[x]);
        x = fa[tp1];
        tp1 = top[x];
    }
    if(deep[x] < deep[y]) swap(x, y);
    Sec_G(1, n, 1, tree[y], tree[x]);
    return ;
}

void Dfs_calc(int l, int r, int jd) {
    if(l == r) {
        if(deep[bef[l]] == tim[bef[l]]) Answer[bef[l]] = W[jd];
        return ;
    }
    if(F[jd]) down(jd);
    int mid = (l + r) >> 1;
    Dfs_calc(l, mid, lson);
    Dfs_calc(mid + 1, r, rson);
}

void work_3(){
    Dfs_son(1, 0, 0);
    Dfs_un(1, 1);
    for(int i = 1; i <= m; i ++) Sec_G_imp(Askl[i], Askr[i]);
    Dfs_calc(1, n, 1);
}

int main()
{
    n = read(); m = read();
    for(int i = 1; i <= n; i ++) head[i] = -1;
    for(int i = 1; i <= n - 1; i ++) {int u = read(); int v = read(); add(u, v); add(v, u);}
    for(int i = 1; i <= n; i ++) tim[i] = read();
    for(int i = 1; i <= m; i ++) Askl[i] = read(), Askr[i] = read();
    if(one_) work_1();
    else if(two_) work_2();
    else if(three_) work_3();
    for(int i = 1; i <= n; i ++) printf("%d ", Answer[i]);
    return 0;
}