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#include<cstdio> #include<cstdlib> #include<cmath> #include<cstring> #include<algorithm> #define rep(i,x,y) for(register int i=x;i<=y;++i) #define repd(i,x,y) for(register int i=x;i>=y;--i) #define ll long long #define lowbit(x) x&(-x) using namespace std; const int N=2e5+50; int n,m,id[N],rt[N<<2],top[N],hson[N],size[N],deep[N],head[N],f[N],x,y,op,cnt; struct { int v,nxt; inline void init(int a,int b){v=a;nxt=b;} }e[N]; inline void adde(int u,int v){ e[++cnt].init(v,head[u]); head[u]=cnt; } void dfs1(int x){ size[x]=1; for(int i=head[x],v;i;i=e[i].nxt)if((v=e[i].v)!=f[x]){ f[v]=x; deep[v]=deep[x]+1; dfs1(v); size[x]+=size[v]; if(size[hson[x]]<size[v])hson[x]=v; } } void dfs2(int x,int t){ top[x]=t;id[x]=++cnt; if(hson[x])dfs2(hson[x],t); for(int i=head[x],v;i;i=e[i].nxt)if(hson[x]!=(v=e[i].v)&&v!=f[x])dfs2(v,v); } inline void update(int x,int y){for(register int i=x;i<=n;i+=lowbit(i))rt[i]+=y;} inline int query(int x){int ans=0;for(register int i=x;i;i-=lowbit(i))ans+=rt[i];return ans;} inline int check(int x,int y){ while(top[x]!=top[y]){ if(deep[top[x]]<deep[top[y]])swap(x,y); if(query(id[x])-query(id[top[x]]-1))return 0; x=f[top[x]]; } if(id[x]<id[y])swap(x,y); return query(id[x])-query(id[y]-1)==0; }
int main(){ scanf("%d%d",&n,&m); rep(i,2,n){ scanf("%d%d",&x,&y); adde(x,y);adde(y,x); } dfs1(1);cnt=0; dfs2(1,1); while(m--){ scanf("%d",&op); if(op==1){ scanf("%d%d",&x,&y); puts(check(x,y)?"YES":"NO"); } else if(op==2){scanf("%d",&x);update(id[x],-1);} else {scanf("%d",&x);update(id[x],1);} } return 0; }
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