|BZOJ 4196|树链剖分|线段树|[Noi2015]软件包管理器

BZOJ 4196

树链剖分支持修改查找子树和到根的路径权值和即可解决，注意pushdown放前面注意lc，rc会爆的情况

#include<cstdio>#include<cstring>#include<algorithm>#define fo(i, j, k) for (i=(j);i<=(k);i++)#define fd(i, k, j) for (i=(k);i>=(j);i--)#define fe(i, u) for (i=head[u];i!=-1;i=e[i].next)#define rd(a) scanf("%d", &a)#define rd2(a, b) scanf("%d%d", &a, &b)#define rd3(a, b, c) scanf("%d%d%d", &a, &b, &c)#define ms(i, j) memset(i, j, sizeof i)#define FN2 "bzoj4196" using namespace std;const int MAXN = 100000 + 500;int n, head[MAXN], cnt;int p[MAXN], dep[MAXN], fa[MAXN], top[MAXN], son[MAXN], siz[MAXN], pre, ll[MAXN], rr[MAXN];struct data{int to, next;}e[MAXN*2];void dfs1(int u, int pa) {    int i;     dep[u] = dep[pa] + 1, fa[u] = pa, siz[u] = 1;    fe (i, u) {        int v = e[i].to;        if (v!=pa) {            dfs1(v, u);            siz[u] += siz[v];            if (son[u]==-1||siz[son[u]]<siz[v]) son[u] = v;        }    }}void dfs2(int u, int chain) {    int i;    p[u] = ++pre, top[u] = chain, ll[u] = pre;    if (son[u]!=-1) {        dfs2(son[u], chain);        fe (i, u) {            int v = e[i].to;            if (v!=fa[u]&&v!=son[u]) dfs2(v, v);        }    }    rr[u] = pre;}int sumv[MAXN*4], lazy[MAXN*4];#define lc (o<<1)#define rc (o<<1|1)#define M ((l+r)>>1)void pushup(int o) {    sumv[o] = sumv[lc] + sumv[rc];}void pushdown(int o, int len) {    if (len==1) return ;    if (lazy[o]!=-1) {        lazy[lc] = lazy[rc] = lazy[o];        sumv[lc] = lazy[o] * (len-len/2);        sumv[rc] = lazy[o] * (len/2);        lazy[o] = -1;    }}void update(int o, int l, int r, int x, int y, int v) {    pushdown(o, r-l+1);    if (x<=l&&r<=y) {        lazy[o] = v;        sumv[o] = v * (r-l+1);        return ;    }    if (x<=M) update(lc,l,M,x,y,v);    if (M<y)  update(rc,M+1,r,x,y,v);    pushup(o);}int query(int o, int l, int r, int x, int y) {    pushdown(o, r-l+1);    int ret = 0;    if (x<=l&&r<=y) {        return sumv[o];    }    if (x<=M) ret += query(lc,l,M,x,y);    if (M<y)  ret += query(rc,M+1,r,x,y);    return ret;}int findRoute(int u, int v) {    int f1 = top[u], f2 = top[v], ret = 0, tot = 0;    while (f1!=f2) {        if (dep[f1]<dep[f2]) swap(f1, f2), swap(u, v);         ret += query(1,1,n,p[f1],p[u]);        tot += p[u] - p[f1] + 1;        u = fa[f1];        f1 = top[u];    }    if (dep[u]<dep[v]) swap(u, v);    ret += query(1,1,n,p[v],p[u]);    tot += p[u] - p[v] + 1;    return tot - ret;}int changeRoute(int u, int v, int c) {    int f1 = top[u], f2 = top[v];    while (f1!=f2) {        if (dep[f1]<dep[f2]) swap(f1, f2), swap(u, v);         update(1,1,n,p[f1],p[u],c);        u = fa[f1];        f1 = top[u];    }    if (dep[u]<dep[v]) swap(u, v);    update(1,1,n,p[v],p[u],c);}int findSub(int u) {    int ret = query(1,1,n,ll[u],rr[u]);    return ret;}int changeSub(int u, int c) {    update(1,1,n,ll[u],rr[u],c);}void ins(int u, int v) {    ++cnt; e[cnt].to = v, e[cnt].next = head[u], head[u] = cnt;    ++cnt; e[cnt].to = u, e[cnt].next = head[v], head[v] = cnt; }void init() {    int i; pre = cnt = 0;    fo (i, 1, n) head[i] = -1, p[i] = 0, dep[i] = 0, fa[i] = 0, top[i] = 0, son[i] = -1, siz[i] = 0, ll[i] = rr[i] = 0;    fo (i, 1, 2*n) e[i].to = 0, e[i].next = -1;    fo (i, 1, 4*n) sumv[i] = 0, lazy[i] = -1;    fo (i, 1, n-1) {        int a; rd(a); ins(a+1, i+1);    }}void solve() {    int i;    dfs1(1, 0), dfs2(1, 1);    int q, x; rd(q);    char ch[20];    fo (i, 1, q) {        scanf("%s", ch);        if (ch[0]=='i') {            rd(x);            printf("%d\n", findRoute(x+1, 1));            changeRoute(x+1,1,1);        } else {            rd(x);            printf("%d\n", findSub(x+1));            changeSub(x+1,0);        }    }}int main() {    #ifndef ONLINE_JUDGE    freopen(FN2".in","r",stdin);freopen("1.out","w",stdout);    #endif    while (rd(n)==1) init(), solve();    return 0;}