#include <bits/stdc++.h>
#define ll long long
#define F(i,a,b) for (int i=a; i<=b; i++)
#define F1(i,a,b) for (int i=a; i<b; i++)
#define pb push_back
using namespace std;
const int MN=1e5+5;
struct segt{
	ll dat,add;
}tree[MN*4];
int N,M,R,P,size[MN],verw[MN],fa[MN],root,wson[MN],top[MN],dfn[MN],vistime,tnum,depth[MN],id[MN];
vector<int> G[MN];
void build(int p,int l,int r){
	if(l==r){tree[p].dat=verw[id[l]]; return ;}
	int mid=(l+r)>>1,A=p*2,B=p*2+1;
	build(A,l,mid);
	build(B,mid+1,r);
	tree[p].dat=tree[A].dat+tree[B].dat;
}
void pdown(int p,int l,int r){
	int mid=(l+r)>>1,A=p*2,B=p*2+1;	
	tree[A].add+=tree[p].add,tree[B].add+=tree[p].add;
	tree[A].dat+=tree[p].add*(mid-l+1), tree[B].dat+=tree[p].add*(r-mid);
	tree[A].dat%=P,tree[B].dat%=P;
	tree[A].add%=P,tree[B].add%=P;
	tree[p].add=0;
}
void change(int p,int l,int r,int cl,int cr,int cnum){
	if(cl<=l&&r<=cr){tree[p].dat+=(l-r+1)*cnum; tree[p].add+=cnum; return ;}
	int mid=(l+r)>>1,A=p*2,B=p*2+1;
	pdown(p,l,r);	
	if(cl<=mid) change(A,l,mid,cl,cr,cnum);
	if(cr>=mid+1) change(B,mid+1,r,cl,cr,cnum);
	tree[p].dat=(tree[A].dat+tree[B].dat)%P;	
}
ll ask(int p,int l,int r,int fl,int fr){
	if(fl<=l && r<=fr) return tree[p].dat;
	int mid=(l+r)>>1,A=p*2,B=p*2+1;
	pdown(p,l,r);
	ll res=0;
	if(fl<=mid) res+=ask(A,l,mid,fl,fr);
	if(fr>=mid+1) res+=ask(B,mid+1,r,fl,fr);
	return res%P;
}
void dfs1(int u){
	size[u]=1;
	depth[u]=depth[fa[u]]+1;
	for(auto v:G[u]) if(v!=fa[u]){
		fa[v]=u;
		dfs1(v);
		size[u]+=size[v];
		if(size[v]>size[wson[u]]) wson[u]=v;
	}	
}
void dfs2(int u,int frt){
	dfn[u]=++vistime;
	id[vistime]=u;
	top[u]=frt;
	if(wson[u]) dfs2(wson[u],frt);
	for(auto v:G[u]) if(v!=fa[u] && v!=wson[u]) dfs2(v,v);
}
void apath(int s,int t,int cnum){
	while(top[s]!=top[t]){
		if(depth[top[s]]<depth[top[t]]) swap(s,t);
		change(1,1,N,dfn[top[s]],dfn[s],cnum);
		s=fa[top[s]];
	}
	if(depth[s]>depth[t]) swap(s,t);
	change(1,1,N,dfn[s],dfn[t],cnum);
}
ll qpath(int s,int t){
	ll res=0;
	while(top[s]!=top[t]){
		if(depth[top[s]]<depth[top[t]]) swap(s,t);
		res=(ask(1,1,N,dfn[top[s]],dfn[s])+res)%P;
		s=fa[top[s]];
	}
	if(depth[s]>depth[t]) swap(s,t);
	res=(ask(1,1,N,dfn[s],dfn[t])+res)%P;
	return res;
}
void ason(int x,int cnum){
	change(1,1,N,dfn[x],dfn[x]+size[x]-1,cnum);
}
ll qson(int x){
	return ask(1,1,N,dfn[x],dfn[x]+size[x]-1)%P;
}
int main(){
//	freopen("qaq.in","r",stdin);
	cin>>N>>M>>R>>P;
	F(i,1,N) cin>>verw[i];
	F(i,1,N-1) {int u,v;cin>>u>>v;G[u].pb(v),G[v].pb(u);}
	dfs1(R);
	dfs2(R,R);
	build(1,1,N);
	F(i,1,M){
		int opt,x,y,z;
		cin>>opt;
		if(opt==1){
			cin>>x>>y>>z;
			apath(x,y,z);
		} else if (opt==2){
			cin>>x>>y;
			cout<<qpath(x,y)<<endl;
		} else if(opt==3){
			cin>>x>>z;
			ason(x,z);
		} else if(opt==4){
			cin>>x;
			cout<<qson(x)<<endl;
		}
	}
	return 0;
}

错误数据

8 10 6 623232
56 838 680 614 846 408 890 829 
1 2
2 3
3 4
1 5
4 7
4 8
7 6
3 4 859
1 4 2 189
2 1 7

悬赏关注两个 谢谢大佬了