洛谷3384&bzoj1036树链剖分

值得注意的是：

一个点的子树是存在一起的。。。也就是说我们修改子树的时候只用。。。

/**************************************************************
    Problem: 1036
    User: Ez3real
    Language: C++
    Result: Accepted
    Time:3068 ms
    Memory:8112 kb
****************************************************************/

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<algorithm>
#define l(x) (x<<1)
#define r(x) ((x<<1)|1)
#define ll long long
using namespace std;
struct Treenode{int l,r;ll tag,val,mx;};
struct Segtree
{
    Treenode tr[*];
    void pushup(int id){tr[id].val=tr[l(id)].val+tr[r(id)].val;}
    void pushdown(int id)
    {
        tr[l(id)].val+=tr[id].tag*(tr[l(id)].r-tr[l(id)].l+);
        tr[r(id)].val+=tr[id].tag*(tr[r(id)].r-tr[r(id)].l+);
        tr[l(id)].tag+=tr[id].tag;tr[r(id)].tag+=tr[id].tag;
        tr[id].tag=;
    }
    void build(int id,int L,int R)
    {
        tr[id].l=L,tr[id].r=R;
        tr[id].tag=;
        if(L==R)return;
        int mid=(L+R)>>;
        build(l(id),L,mid);
        build(r(id),mid+,R);
        pushup(id);
    }
    void update(int id,int L,int R,ll k)
    {
        if(tr[id].l>=L && tr[id].r<=R)
        {
            tr[id].val+=k*(tr[id].r-tr[id].l+);
            tr[id].tag+=k;
            return;
        }
        if(tr[id].tag)pushdown(id);
        int mid=(tr[id].l+tr[id].r)>>;
        if(L<=mid)update(l(id),L,R,k);
        if(R>mid) update(r(id),L,R,k);
        pushup(id);
    }
    ll query(int id,int L,int R)
    {
        if(tr[id].l>=L && tr[id].r<=R)return tr[id].val;
        if(tr[id].tag)pushdown(id);
        int mid=(tr[id].l+tr[id].r)>>;
        ll ans=;
        if(L<=mid)ans+=query(l(id),L,R);
        if(R>mid)ans+=query(r(id),L,R);
        return ans;
    }
}Seg;

int first[],to[*],next[*];
ll val[*],cnt;
int size[],depth[],fa[],pos[],bl[],sz;
inline void add(int u,int v){to[++cnt]=v;next[cnt]=first[u];first[u]=cnt;}
int n,q,r,P;
inline void dfs1(int u)
{
    size[u]=;
    for(int i=first[u];i;i=next[i])
    {
        if(to[i]==fa[u])continue;
        depth[to[i]]=depth[u]+;
        fa[to[i]]=u;
        dfs1(to[i]);
        size[u]+=size[to[i]];
    }
}
inline void dfs2(int u,int idc)
{
    int k=;
    sz++;
    pos[u]=sz;
    bl[u]=idc;
    for(int i=first[u];i;i=next[i])
        if(depth[to[i]]>depth[u] && size[to[i]]>size[k])
            k=to[i];

    if(k==)return;
    dfs2(k,idc);
    for(int i=first[u];i;i=next[i])
        if(depth[to[i]]>depth[u] && k!=to[i])
            dfs2(to[i],to[i]);
}
void tradd(ll x,ll v){Seg.update(,pos[x],pos[x]+size[x]-,v);}
ll trq(ll x){return Seg.query(,pos[x],pos[x]+size[x]-)%P;}
void Chainadd(ll x,ll y,ll v)
{
    while(bl[x]!=bl[y])
    {
        if(depth[bl[x]]<depth[bl[y]]){x^=y;y^=x;x^=y;}
        Seg.update(,pos[bl[x]],pos[x],v);
        x=fa[bl[x]];
    }
    if(depth[x]<depth[y]){x^=y;y^=x;x^=y;}
    Seg.update(,pos[y],pos[x],v);
}
ll Qsum(ll u,ll v)
{
    ll sum=;
    while(bl[u]!=bl[v])
    {
        if(depth[bl[u]]<depth[bl[v]]){u^=v;v^=u;u^=v;}
        (sum+=Seg.query(,pos[bl[u]],pos[u]))%=P;
        u=fa[bl[u]];
    }
    if(depth[u]<depth[v]){u^=v;v^=u;u^=v;}
    (sum+=Seg.query(,pos[v],pos[u]))%=P;
    return sum;
}
void Solve()
{
    scanf("%d%d%d%d",&n,&q,&r,&P);
    for(int i=;i<=n;i++)scanf("%lld",&val[i]);
    for(int i=;i<n;i++)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        add(x,y);
        add(y,x);
    }
    depth[r]=;
    dfs1(r);
    dfs2(r,r);
    Seg.build(,,n);
    for(int i=;i<=n;i++)Seg.update(,pos[i],pos[i],val[i]);
    for(int i=;i<=q;i++)
    {
        int opt;
        scanf("%d",&opt);
        if(opt==)
        {
            ll x,y,w;
            scanf("%lld%lld%lld",&x,&y,&w);
            Chainadd(x,y,w);
        }
        if(opt==)
        {
            ll x,y;
            scanf("%lld%lld",&x,&y);
            printf("%lld\n",Qsum(x,y));
        }
        if(opt==)
        {
            ll x,v;
            scanf("%lld%lld",&x,&v);
            tradd(x,v);
        }
        if(opt==)
        {
            ll x;
            scanf("%lld",&x);
            printf("%lld\n",trq(x));
        }
    }
}
int main()
{
    Solve();
    return ;
}

Luogu3384

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<algorithm>
#define l(x) (x<<1)
#define r(x) ((x<<1)|1)
#define ll long long
using namespace std;

struct Treenode{int l,r;ll tag,val,mx;};
struct Segtree
{
    Treenode tr[*];
    void pushup(int id){tr[id].val=tr[l(id)].val+tr[r(id)].val;tr[id].mx=max(tr[l(id)].mx,tr[r(id)].mx);}
    void build(int id,int L,int R)
    {
        tr[id].l=L,tr[id].r=R;
        if(L==R)return;
        int mid=(L+R)>>;
        build(l(id),L,mid);
        build(r(id),mid+,R);
        pushup(id);
    }
    void update(int k,int x,int y)
    {
        int l=tr[k].l,r=tr[k].r,mid=(l+r)>>;
        if(l==r){tr[k].val=tr[k].mx=y;return;}
        if(x<=mid)update(k<<,x,y);
        else update(k<<|,x,y);
        tr[k].val=tr[k<<].val+tr[k<<|].val;
        tr[k].mx=max(tr[k<<].mx,tr[k<<|].mx);
    }
    int query(int id,int L,int R)
    {
        if(tr[id].l>=L && tr[id].r<=R)return tr[id].val;
        int mid=(tr[id].l+tr[id].r)>>;
        int ans=;
        if(L<=mid)ans+=query(l(id),L,R);
        if(R>mid)ans+=query(r(id),L,R);
        return ans;
    }
    int Query(int id,int L,int R)
    {
        if(tr[id].l>=L && tr[id].r<=R)return tr[id].mx;
        int mid=(tr[id].l+tr[id].r)>>;
        int ans=-;
        if(L<=mid)ans=max(ans,Query(l(id),L,R));
        if(R>mid)ans=max(ans,Query(r(id),L,R));
        return ans;
    }
}Seg;

int first[],to[*],next[*],val[*],cnt;
int size[],depth[],fa[],pos[],bl[],sz;
inline void add(int u,int v){to[++cnt]=v;next[cnt]=first[u];first[u]=cnt;}
inline void dfs1(int u)
{
    size[u]=;
    for(int i=first[u];i;i=next[i])
    {
        if(to[i]==fa[u])continue;
        depth[to[i]]=depth[u]+;
        fa[to[i]]=u;
        dfs1(to[i]);
        size[u]+=size[to[i]];
    }
}
inline void dfs2(int u,int idc)
{
    int k=;
    sz++;
    pos[u]=sz;
    bl[u]=idc;
    for(int i=first[u];i;i=next[i])
        if(depth[to[i]]>depth[u] && size[to[i]]>size[k])
            k=to[i];

    if(k==)return;
    dfs2(k,idc);
    for(int i=first[u];i;i=next[i])
        if(depth[to[i]]>depth[u] && k!=to[i])
            dfs2(to[i],to[i]);
}
int Qsum(int u,int v)
{
    int sum=;
    while(bl[u]!=bl[v])
    {
        if(depth[bl[u]]<depth[bl[v]]){u^=v;v^=u;u^=v;}
        sum+=Seg.query(,pos[bl[u]],pos[u]);
        u=fa[bl[u]];
    }
    if(pos[u]>pos[v]){u^=v;v^=u;u^=v;}
    sum+=Seg.query(,pos[u],pos[v]);
    return sum;
}
int Qmax(int u,int v)
{
    int mx=-;
    while(bl[u]!=bl[v])
    {
        if(depth[bl[u]]<depth[bl[v]]){u^=v;v^=u;u^=v;}
        mx=max(mx,Seg.Query(,pos[bl[u]],pos[u]));
        u=fa[bl[u]];
    }
    if(pos[u]>pos[v]){u^=v;v^=u;u^=v;}
    mx=max(mx,Seg.Query(,pos[u],pos[v]));
    return mx;
}
int n,q;
void Solve()
{
    scanf("%d",&n);
    for(int i=;i<n;i++)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        add(x,y);
        add(y,x);
    }
    for(int i=;i<=n;i++)scanf("%d",&val[i]);
    dfs1();
    dfs2(,);
    Seg.build(,,n);
    for(int i=;i<=n;i++)Seg.update(,pos[i],val[i]);
    scanf("%d",&q);
    char ch[];
    for(int i=;i<=q;i++)
    {
        int x,y;scanf("%s%d%d",ch,&x,&y);
        if(ch[]=='C'){val[x]=y;Seg.update(,pos[x],y);}
        else
        {
            if(ch[]=='M')printf("%d\n",Qmax(x,y));
            else printf("%d\n",Qsum(x,y));
        }
    }
}
int main()
{
    Solve();
    return ;
}

bzoj1036