BZOJ1036: [ZJOI2008]树的统计Count

#include <cstdio>
#include <iostream>
#include <queue>
#include <vector>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <stack>
#define N 30005
#define M 200005
#define INF 1e9
#define mod 1000000
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pa;

int read()
{
int x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-') f=-1;ch=getchar();}
while(isdigit(ch)){x=(x<<1)+(x<<3)+ch-'0';ch=getchar();}
return x*f;
}

int n,m,cnt,ind,T;
int b[N<<1],p
,nextedge[N<<1];
int deep
,fa
,son
,sz
,pos
,ftree
,top
,a
;

class Seg_Tree{
public:
int l,r,mx,sum;
}e[N<<2];

void Add(int x,int y)
{
cnt++;
b[cnt]=y;
nextedge[cnt]=p[x];
p[x]=cnt;
}

void Anode(int x,int y){
Add(x,y);Add(y,x);
}

void Input_Init()
{
n=read();
for(int i=1;i<n;i++)
{
static int x,y;
x=read(),y=read();
Anode(x,y);
}
for(int i=1;i<=n;i++) a[i]=read();
}

void Dfs(int x)
{
sz[x]=1;
for(int i=p[x];i;i=nextedge[i])
{
int v=b[i];
if(v==fa[x]) continue;
deep[v]=deep[x]+1;fa[v]=x;
Dfs(v);sz[x]+=sz[v];
son[x]=sz[son[x]]>sz[v]?son[x]:v;
}
}

void dfs(int x,int root)
{
pos[x]=++ind;ftree[pos[x]]=x;
top[x]=root;
if(!son[x]) return;
dfs(son[x],root);
for(int i=p[x];i;i=nextedge[i])
{
int v=b[i];
if(v!=fa[x]&&v!=son[x]) dfs(v,v);
}
}

void pushup(int p){
e[p].mx=max(e[p<<1].mx,e[p<<1|1].mx);
e[p].sum=e[p<<1].sum+e[p<<1|1].sum;
}

void Build(int p,int l,int r)
{
e[p].l=l,e[p].r=r;
if(l==r)
{
e[p].mx=e[p].sum=a[ftree[l]];
return;
}
int mid=l+r>>1;
Build(p<<1,l,mid);Build(p<<1|1,mid+1,r);
pushup(p);
}

void Solve_Change(int p,int x,int y)
{
int l=e[p].l,r=e[p].r,mid=l+r>>1;
if(l==x&&r==x)
{
e[p].mx=e[p].sum=y;
return;
}
if(x<=mid) Solve_Change(p<<1,x,y);
else Solve_Change(p<<1|1,x,y);
pushup(p);
}

int Query_Max(int p,int x,int y)
{
int l=e[p].l,r=e[p].r,mid=l+r>>1;
if(l==x&&y==r)
return e[p].mx;
if(y<=mid) return Query_Max(p<<1,x,y);
if(x>mid) return Query_Max(p<<1|1,x,y);
return max(Query_Max(p<<1,x,mid),Query_Max(p<<1|1,mid+1,y));
}

void Solve_Max(int x,int y)
{
int fx=top[x],fy=top[y];
int rtn=-INF;
while(fx!=fy)
{
if(deep[fx]<deep[fy]) swap(x,y),swap(fx,fy);
rtn=max(rtn,Query_Max(1,pos[fx],pos[x]));
x=fa[fx],fx=top[x];
}
if(deep[x]<deep[y]) swap(x,y);
rtn=max(rtn,Query_Max(1,pos[y],pos[x]));
printf("%d\n",rtn);
}

int Query_Sum(int p,int x,int y)
{
int l=e[p].l,r=e[p].r,mid=l+r>>1;
if(l==x&&y==r)
return e[p].sum;
if(y<=mid) return Query_Sum(p<<1,x,y);
if(x>mid) return Query_Sum(p<<1|1,x,y);
return Query_Sum(p<<1,x,mid)+Query_Sum(p<<1|1,mid+1,y);
}

void Solve_Sum(int x,int y)
{
int fx=top[x],fy=top[y];
int rtn=0;
while(fx!=fy)
{
if(deep[fx]<deep[fy]) swap(x,y),swap(fx,fy);
rtn+=Query_Sum(1,pos[fx],pos[x]);
x=fa[fx],fx=top[x];
}
if(deep[x]<deep[y]) swap(x,y);
rtn+=Query_Sum(1,pos[y],pos[x]);
printf("%d\n",rtn);
}

void Solve()
{
m=read();
char ch[10];static int x,y;
while(m--)
{
scanf("%s",ch);x=read(),y=read();
if(ch[1]=='M') Solve_Max(x,y);
else if(ch[1]=='S') Solve_Sum(x,y);
else Solve_Change(1,pos[x],y);
}
}

int main()
{
Input_Init();
Dfs(1
10153
);dfs(1,1);Build(1,1,n);
Solve();
return 0;
}

#include <cstdio>
#include <iostream>
#include <queue>
#include <vector>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <stack>
#define N 30005
#define M 2001005
#define INF 1e9
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pa;

int read()
{
int x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-') f=-1;ch=getchar();}
while(isdigit(ch)){x=(x<<1)+(x<<3)+ch-'0';ch=getchar();}
return x*f;
}

int n,m,top,cnt;
int b[N<<1],p
,nextedge[N<<1];
int mx
,tag
,a
,son
[2],st
,fa
,sum
;
bool rev
;

void Add(int x,int y)
{
cnt++;
b[cnt]=y;
nextedge[cnt]=p[x];
p[x]=cnt;
}

void Anode(int x,int y){
Add(x,y);Add(y,x);
}

void dfs(int x)
{
for(int i=p[x];i;i=nextedge[i])
{
int v=b[i];
if(v==fa[x]) continue;
fa[v]=x;dfs(v);
}
}

void Input_Init()
{
n=read();mx[0]=-INF;
for(int i=1;i<n;i++)
{
static int x,y;
x=read(),y=read();
Anode(x,y);
}
for(int i=1;i<=n;i++) sum[i]=a[i]=mx[i]=read();
dfs(1);
}

bool isroot(int x){
return son[fa[x]][0]!=x&&son[fa[x]][1]!=x;
}

void pushup(int k)
{
int l=son[k][0],r=son[k][1];
mx[k]=max(max(mx[l],mx[r]),a[k]);
sum[k]=sum[l]+sum[r]+a[k];
}

void pushdown(int k)
{
int l=son[k][0],r=son[k][1];
if(rev[k])
{
rev[k]=0;rev[l]^=1;rev[r]^=1;
swap(son[k][0],son[k][1]);
}
}

void Rotate(int x)
{
int y=fa[x],z=fa[y],l,r;
l=son[y][1]==x;r=l^1;
if(!isroot(y)) son[z][son[z][1]==y]=x;
fa[x]=z;fa[y]=x;fa[son[x][r]]=y;
son[y][l]=son[x][r];son[x][r]=y;
pushup(y);pushup(x);
}

void Splay(int x)
{
top=0;st[++top]=x;
for(int i=x;!isroot(i);i=fa[i]) st[++top]=fa[i];
while(top) pushdown(st[top--]);
while(!isroot(x))
{
int y=fa[x],z=fa[y];
if(!isroot(y)) {
if(son[z][0]==y^son[y][0]==x) Rotate(x);
else Rotate(y);
}
Rotate(x);
}
}

void Access(int x)
{
for(int t=0;x;t=x,x=fa[x])
Splay(x),son[x][1]=t,pushup(x);
}

void Make_Root(int x){
Access(x);Splay(x);rev[x]^=1;
}

void Solve_Change(int x,int y){
Splay(x);mx[x]=sum[x]=a[x]=y;
pushup(x);
}

void Solve_Max(int x,int y)
{
Make_Root(x);Access(y);Splay(y);
printf("%d\n",mx[y]);
}

void Solve_Sum(int x,int y)
{
Make_Root(x);Access(y);Splay(y);
printf("%d\n",sum[y]);
}

void Solve()
{
m=read();
while(m--)
{
char ch[10];static int x,y;
scanf("%s",ch);x=read(),y=read();
if(ch[0]=='C') Solve_Change(x,y);
else if(ch[1]=='M') Solve_Max(x,y);
else Solve_Sum(x,y);
}
}

int main()
{
Input_Init();
Solve();
return 0;
}