[HAOI2015] chain split tree operation tree

[HAOI2015] chain split tree operation tree

Face questions

Bare sectional tree, segment tree withlazy tag

#include <cstdio>
#include <algorithm>
#define MAXN 100010
#define ll long long
#define sl (x<<1)
#define sr (x<<1|1)
using namespace std;
int head[MAXN],vv[MAXN*2],nxt[MAXN*2],tot;
inline void add_edge(int u, int v){
    vv[++tot]=v;
    nxt[tot]=head[u];
    head[u]=tot;
}
int n;
ll w[MAXN];
int fa[MAXN],sz[MAXN],mxs[MAXN],dep[MAXN];
void dfs1(int u, int f){
    fa[u]=f;
    dep[u]=dep[f]+1;
    sz[u]=1;
    int mxsz=-1;
    for(int i=head[u];i;i=nxt[i]){
        int v=vv[i];
        if(v==f) continue;
        dfs1(v, u);
        sz[u]+=sz[v];
        if(mxsz<sz[v]){
            mxsz=sz[v];
            mxs[u]=v;
        }
    }
}
int topf[MAXN],idx[MAXN],cnt;
ll wnew[MAXN];
void dfs2(int u, int top){
    idx[u]=++cnt;
    wnew[cnt]=w[u];
    topf[u]=top;
    if(mxs[u]==0) return;
    dfs2(mxs[u], top);
    for(int i=head[u];i;i=nxt[i]){
        int v=vv[i];
        if(v==fa[u]||v==mxs[u]) continue;
        dfs2(v,v);
    }
}
struct nod{
    ll sum,lazy;
} tre[MAXN*4];
void push_up(int x){
    tre[x].sum=tre[sl].sum+tre[sr].sum;
}
void buildt(int x, int l, int r){
    if(l==r){
        tre[x].sum=wnew[l];
        return;
    }
    int mid=(l+r)>>1;
    buildt(sl, l, mid);
    buildt(sr, mid+1, r);
    push_up(x);
}
void push_down(int x, int l, int r){
    if(tre[x].lazy==0) return;
    tre[sl].lazy+=tre[x].lazy;
    tre[sr].lazy+=tre[x].lazy;
    int mid=(l+r)>>1;
    tre[sl].sum+=tre[x].lazy*(mid-l+1);
    tre[sr].sum+=tre[x].lazy*(r-(mid+1)+1);
    tre[x].lazy=0;
}
void change(int x, int l, int r, int cl, int cr, ll val){
    if(cl<=l&&r<=cr){
        tre[x].sum+=val*(r-l+1);
        tre[x].lazy+=val;
        return;
    }
    push_down(x, l, r);
    int mid=(l+r)>>1;
    if(cl<=mid) change(sl, l, mid, cl, cr, val);
    if(mid<cr) change(sr, mid+1, r, cl, cr, val);
    push_up(x);
}
ll query(int x, int l, int r, int ql, int qr){
    if(ql<=l&&r<=qr){
        return tre[x].sum;
    }
    push_down(x, l, r);
    int mid=(l+r)>>1;
    ll ans=0;
    if(ql<=mid) ans+=query(sl, l, mid, ql, qr);
    if(mid<qr) ans+=query(sr, mid+1, r, ql, qr);
    return ans;
}
ll tre_query(int a, int b){
    ll ans=0;
    while(topf[a]!=topf[b]){
        if(dep[topf[a]]<dep[topf[b]]) swap(a,b);
        ans+=query(1, 1, n, idx[topf[a]], idx[a]);
        a=fa[topf[a]];
    }
    if(dep[a]<dep[b]) swap(a,b);
    ans+=query(1, 1, n, idx[b], idx[a]);
    return ans;
}
void tre_change(int a, int val){
    change(1, 1, n, idx[a], idx[a]+sz[a]-1, val);
}
int main()
{
    scanf("%d", &n);
    int q;
    scanf("%d", &q);
    for(int i=1;i<=n;++i) scanf("%lld", &w[i]);
    for(int i=1;i<n;++i){
        int a,b;
        scanf("%d %d", &a, &b);
        add_edge(a,b);
        add_edge(b,a);
    }
    dfs1(1,1);
    dfs2(1,1);
    buildt(1, 1, n);
    while(q--){
        int type;
        scanf("%d", &type);
        int x;
        ll a;
        if(type==1){
            scanf("%d %lld", &x, &a);
            change(1, 1, n, idx[x], idx[x], a);
        }else if(type==2){
            scanf("%d %lld", &x, &a);
            tre_change(x, a);
        }else{
            scanf("%d", &x);
            printf("%lld\n", tre_query(x, 1));
        }
    }
    return 0;
}