【模板】树链剖分

留坑待补，先放代码

#include<iostream>
#include<cstdio>
#include<cstring>
#include<bitset>
#include<queue>
#include<algorithm>
#define int long long
#define rii register int i
#define rij register int j
using namespace std;
int n,m,r,p;
struct ljb{
    int to,nxt;
}x[400005];
struct node{
    int val,lazy;
}y[600005];
int f[200005],sd[200005],head[200005],val[200005],size[200005];
int weison[200005],cnt,bnt,nid[200005],nval[200005],ntop[200005];
int res;
void add(int from,int to)
{
    cnt++;
    x[cnt].to=to;
    x[cnt].nxt=head[from];
    head[from]=cnt;
}
void dfs1(int wz,int fa,int s)
{
    sd[wz]=s;
    f[wz]=fa;
    size[wz]=1;
    int maxn=0;
    for(rii=head[wz];i!=0;i=x[i].nxt)
    {
        int to=x[i].to;
        if(to==fa)
        {
            continue;
        }
        dfs1(to,wz,s+1);
        size[wz]+=size[to];
        if(size[to]>maxn)
        {
            maxn=size[to];
            weison[wz]=to;
        }
    }
} 
void dfs2(int wz,int top)
{
    bnt++;
    nid[wz]=bnt;
    nval[bnt]=val[wz];
    ntop[wz]=top;
    if(weison[wz]==0)
    {
        return;
    }
    dfs2(weison[wz],top);
    for(rii=head[wz];i!=0;i=x[i].nxt)
    {
        int to=x[i].to;
        if(weison[wz]==to||f[wz]==to)
        {
            continue;
        }
        dfs2(to,to);
    }
}
void build(int bh,int l,int r)
{
    if(l==r)
    {
        y[bh].val=nval[l];
        y[bh].val%=p;
        return;
    }
    int mid=(l+r)/2;
    build(bh*2,l,mid);
    build(bh*2+1,mid+1,r);
    y[bh].val+=y[bh*2].val+y[bh*2+1].val;
    y[bh].val%=p;
}
void pushdown(int bh,int cd)
{
    y[bh*2].lazy+=y[bh].lazy;
    y[bh*2+1].lazy+=y[bh].lazy;
    y[bh*2].val+=y[bh].lazy*(cd-(cd/2));
    y[bh*2+1].val+=y[bh].lazy*(cd/2);
    y[bh*2].val%=p;
    y[bh*2+1].val%=p;
    y[bh].lazy=0;
}
void updata(int bh,int nl,int nr,int l,int r,int val)
{
    int len=(nr-nl+1);    
    if(l<=nl&&nr<=r)
    {
        y[bh].lazy+=val;
        y[bh].val+=val*len;
        y[bh].val%=p;
        return;
    }
    if(y[bh].lazy!=0)
    {
        pushdown(bh,len);
    }
    int mid=(nl+nr)/2;
    if(l<=mid)
    {
        updata(bh*2,nl,mid,l,r,val);
    }
    if(r>mid)
    {
        updata(bh*2+1,mid+1,nr,l,r,val);
    }
    y[bh].val=(y[bh*2].val+y[bh*2+1].val)%p;
}
void query(int bh,int nl,int nr,int l,int r)
{
    if(l<=nl&&r>=nr)
    {
        res+=y[bh].val;
        res%=p;
        return; 
    }
    int mid=(nl+nr)/2;
    if(y[bh].lazy!=0)
    {
        pushdown(bh,nr-nl+1); 
    }
    if(l<=mid)
    {
        query(bh*2,nl,mid,l,r);
    }
    if(r>mid)
    {
        query(bh*2+1,mid+1,nr,l,r);
    }
}
int querylj(int from,int to)
{
    int ans=0;
    while(ntop[from]!=ntop[to])
    {
        if(sd[ntop[from]]<sd[ntop[to]])
        {
            swap(from,to);
        }
        res=0;
        query(1,1,n,nid[ntop[from]],nid[from]);
        ans+=res;
        ans%=p;
        from=f[ntop[from]];
    }
    if(sd[from]>sd[to])
    {
        swap(from,to);
    }
    res=0;
    query(1,1,n,nid[from],nid[to]);
    ans+=res;
    ans%=p;
    return ans;
}
void addlj(int from,int to,int val)
{
    val%=p;
    while(ntop[from]!=ntop[to])
    {
        if(sd[ntop[from]]<sd[ntop[to]])
        {
            swap(from,to);
        }
        updata(1,1,n,nid[ntop[from]],nid[from],val);
        from=f[ntop[from]];
    }
    if(sd[from]>sd[to])
    {
        swap(from,to);
    }
    updata(1,1,n,nid[from],nid[to],val);
}
void addson(int wz,int val)
{
    updata(1,1,n,nid[wz],nid[wz]+size[wz]-1,val);
}
int queryson(int wz)
{
    res=0;
    query(1,1,n,nid[wz],nid[wz]+size[wz]-1);
    return res;
}
signed main()
{
    scanf("%lld%lld%lld%lld",&n,&m,&r,&p);
    for(rii=1;i<=n;i++)
    {
        scanf("%lld",&val[i]);
    }
    for(rii=1;i<n;i++)
    {
        int from,to;
        scanf("%lld%lld",&from,&to);
        add(from,to);
        add(to,from);
    }
    dfs1(r,0,2);
    dfs2(r,r);
    build(1,1,n);
    for(rii=1;i<=m;i++)
    {
        int opt,from,to,val,kkk;
        scanf("%lld",&opt);
        if(opt==1)
        {
            scanf("%lld%lld",&from,&to);
            scanf("%lld",&val);
            addlj(from,to,val);
        }
        if(opt==2)
        {
            scanf("%lld%lld",&from,&to);
            kkk=querylj(from,to);
            printf("%lld\n",kkk);
        }
        if(opt==3)
        {
            scanf("%lld%lld",&from,&val);
            addson(from,val);
        }
        if(opt==4)
        {
            scanf("%lld",&from);
            kkk=queryson(from);
            printf("%lld\n",kkk);
        }
    }
}