#include<bits/stdc++.h> #define MAXN 200005 #define MAXM 17 usingnamespace std; inlineintread(){ 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<<3)+(x<<1)+(ch^'0'); ch=getchar(); } return x*f; } vector<int>G[MAXN]; inlinevoidAddEdge(int u,int v){ G[u].push_back(v); } int c[MAXN];//每个点的颜色 int anc[MAXN][MAXM],dep[MAXN]; int euler[MAXN];//欧拉序(出栈入栈都要记录) int L[MAXN],R[MAXN];//左右端点 int tot; voiddfs(int u,int father){ dep[u]=dep[father]+1; anc[u][0]=father; euler[L[u]=++tot]=u; for (registerint i=1;i<MAXM;++i) anc[u][i]=anc[anc[u][i-1]][i-1]; for (registerint i=0;i<G[u].size();++i){ int v=G[u][i]; if (v!=father) dfs(v,u); } euler[R[u]=++tot]=u; } inlineintLCA(int u,int v){ if (dep[u]<dep[v]) swap(u,v); for (registerint i=MAXM-1;i>=0;--i){ if (dep[anc[u][i]]>=dep[v]) u=anc[u][i]; } if (u==v) return u; for (registerint i=MAXM-1;i>=0;--i){ if (anc[u][i]!=anc[v][i]){ u=anc[u][i],v=anc[v][i]; } } return anc[u][0]; }
int n,m;
int b[MAXN];//块编号 structQuery{ int u,v,lca,id,a,b; }q[MAXN]; inlinebooloperator < (const Query &A,const Query &B){//莫队的玄学优化 return (b[A.u]^b[B.u])?b[A.u]<b[B.u]:((b[A.u]&1)?A.v<B.v:A.v>B.v); } int inq[MAXN];//在不在莫队维护的范围内 int ans,cnt[MAXN]; inlinevoidUpdate(int i){//相应地加上/减去元素 if (!inq[i]){//加上 cnt[c[i]]++; if (cnt[c[i]]==1) ans++; inq[i]=true; } else { cnt[c[i]]--; if (cnt[c[i]]==0) ans--; inq[i]=false; } } int Ans[MAXN]; inline Query make_q(int u,int v,int lca,int id,int a,int b){ Query temp; temp.id=id; temp.u=u,temp.v=v; temp.lca=lca; temp.a=a,temp.b=b; return temp; } intmain(){ n=read(),m=read();int Size=sqrt(n);//块大小 for (registerint i=0;i<MAXN;++i){ b[i]=i/Size+1; } for (registerint i=1;i<=n;++i){ c[i]=read(); } int rt; for (registerint i=1;i<=n;++i){ int u=read(),v=read(); if (u==0) rt=v; if (v==0) rt=u; AddEdge(u,v); AddEdge(v,u); } dfs(rt,rt); for (registerint i=1;i<=m;++i){ int u=read(),v=read(),a=read(),b=read(); if (L[u]>L[v]) swap(u,v);//保证这条链是从左往右 int lca=LCA(u,v); if (u==lca) q[i]=make_q(L[u],L[v],0,i,a,b);//u为这条链的顶点 else q[i]=make_q(R[u],L[v],lca,i,a,b); } sort(q+1,q+1+m); int l=1,r=0;//模仿STL队列 for (registerint i=1;i<=m;++i){ while (l<q[i].u) Update(euler[l++]); while (l>q[i].u) Update(euler[--l]); while (r<q[i].v) Update(euler[++r]); while (r>q[i].v) Update(euler[r--]); if (q[i].lca) Update(q[i].lca);//注意处理lca Ans[q[i].id]=ans; if (cnt[q[i].a]&&cnt[q[i].b]&&q[i].a!=q[i].b) Ans[q[i].id]--; if (q[i].lca) Update(q[i].lca); } for (registerint i=1;i<=m;++i){ printf("%d\n",Ans[i]); } }