bzoj4034 [HAOI2015]树上操作(树链剖分)

子树修改，通过dfn序可以变成区间修改。然后就是裸题了。

#include
#include
#define ll long long
#define N 100010
int n,a[N],m,num=0,h[N],dep[N],size[N],son[N],fa[N],top[N],in[N],out[N],dfn=0,w[N];
struct edge{
    int to,next;
}data[N<<1];
struct node{
    ll lazy,sum;
}tree[N<<2];
inline int read(){
    int x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
    return x*f;
}
inline int max(int x,int y){return x>y?x:y;}
inline ll max(ll x,ll y){return x>y?x:y;}
void dfs1(int x){
    size[x]=1;
    for(int i=h[x];i;i=data[i].next){
        int y=data[i].to;
        if(fa[x]==y) continue;
        fa[y]=x;dep[y]=dep[x]+1;dfs1(y);size[x]+=size[y];
        if(size[y]>size[son[x]]) son[x]=y;
    }
}
void dfs2(int x,int tp){
    top[x]=tp;in[x]=++dfn;w[dfn]=a[x];
    if(son[x]) dfs2(son[x],tp);
    for(int i=h[x];i;i=data[i].next){
        int y=data[i].to;
        if(y==son[x]||y==fa[x]) continue;
        dfs2(y,y);
    }
    out[x]=dfn;
}
inline void pushup(int p){
    tree[p].sum=tree[p<<1].sum+tree[p<<1|1].sum;
}
inline void pushdown(int p,int l,int r,int mid){
    if(!tree[p].lazy) return;
    tree[p<<1].lazy+=tree[p].lazy;tree[p<<1|1].lazy+=tree[p].lazy;
    tree[p<<1].sum+=(mid-l+1)*tree[p].lazy;
    tree[p<<1|1].sum+=(r-mid)*tree[p].lazy;
    tree[p].lazy=0;
}
void build(int p,int l,int r){
    if(l==r){tree[p].sum=w[l];return;}
    int mid=l+r>>1;
    build(p<<1,l,mid);build(p<<1|1,mid+1,r);
    pushup(p);
}
void change(int p,int l,int r,int x,int y,ll v){//v也要longlong！！！坑死人。 
    if(x<=l&&r<=y){
        tree[p].lazy+=v;tree[p].sum+=(r-l+1)*v;return;
    }
    int mid=l+r>>1;pushdown(p,l,r,mid);
    if(x<=mid) change(p<<1,l,mid,x,y,v);
    if(y>mid) change(p<<1|1,mid+1,r,x,y,v);
    pushup(p);
}
ll qsum(int p,int l,int r,int x,int y){
    if(x<=l&&r<=y) return tree[p].sum;
    int mid=l+r>>1;pushdown(p,l,r,mid);ll sum=0;
    if(x<=mid) sum+=qsum(p<<1,l,mid,x,y);
    if(y>mid) sum+=qsum(p<<1|1,mid+1,r,x,y);
    return sum;
}
ll query(int x){
    ll sum=0;
    while(top[x]!=1){
        sum+=qsum(1,1,n,in[top[x]],in[x]);
        x=fa[top[x]];
    }
    sum+=qsum(1,1,n,1,in[x]);
    return sum;
}
int main(){
//  freopen("a.in","r",stdin);
    n=read();m=read();
    for(int i=1;i<=n;++i) a[i]=read();
    for(int i=1;iint x=read(),y=read();
        data[++num].to=y;data[num].next=h[x];h[x]=num;
        data[++num].to=x;data[num].next=h[y];h[y]=num;
    }
    dep[1]=1;dfs1(1);dfs2(1,1);build(1,1,n);
    while(m--){
        int op=read(),x=read();
        if(op==1) change(1,1,n,in[x],in[x],read());
        if(op==2) change(1,1,n,in[x],out[x],read());
        if(op==3) printf("%lld\n",query(x));
    }
    return 0;
}