This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define sz(a) (int)(a.size())
#define owo ios_base::sync_with_stdio(0);cin.tie(0);
#define all(a) a.begin(),a.end()
typedef pair<int,int> pii;
const int MAXN = 2e5;
vector<pii>adj[MAXN];
int dep[MAXN],par[18][MAXN],asc[MAXN],dsc[MAXN],val[MAXN],n,k;
char c[250000];
int a[250000],d[250000],ans[250000];
void dfs0(int v,int u,int ww){
for(int i=1;i<=17;i++)par[i][v] = par[i-1][par[i-1][v]];
for(pii z:adj[v]){
int x = z.fi;
int w = z.se;
if(x == u)continue;
val[x] = w;
asc[x] = dsc[x] = dep[v];
if(w > ww || v==1)asc[x] = asc[v];
if(w < ww || v==1)dsc[x] = dsc[v];
dep[x] = dep[v]+1;
par[0][x] = v;
dfs0(x,v,w);
}
}
int jump(int v,int d){
for(int i=0;i<=17 && d;i++){
if(d&1)v=par[i][v];
d/=2;
}
return v;
}
int lca(int v,int u){
if(dep[v] < dep[u])swap(v,u);
v = jump(v,dep[v] - dep[u]);
if(v==u)return v;
for(int i=17;i>=0;i--){
if(par[i][v] != par[i][u]){
v = par[i][v];
u = par[i][u];
}
}
return par[0][v];
}
//want to count number of paths from i to j
//such that i->j is increasing
//and the last edge that touches j is <= t
//let c be the centroid
//call node x a start node if c->x is increasing
//call node x an end node if c->x is decreasing
//can sweepline on their time but overcounting????
//call the join time of node x the time where x is first connected to c
//the add time of end node x the time where the first edge from path c->i is added
//contribution for start node i is number of end nodes with join time > its join time and add time <= t
//ok so sweepline backwards by join time then pick whatever sum aggre ds,fenwick should be fast enough
vector<int>cq[MAXN];
int sub[MAXN],join[MAXN],reach[MAXN],fen[250000];
bool ded[MAXN];
void upd(int i,int x){
for(;i<=240000;i+=i&(-i))fen[i]+=x;
}
int query(int i){
int res = 0;
for(;i;i-=i&(-i))res+=fen[i];
return res;
}
void get(int v,int u){
sub[v] = 1;
for(auto x:adj[v]){
if(x.fi==u ||ded[x.fi])continue;
get(x.fi,v);
sub[v]+=sub[x.fi];
}
}
int cen(int v,int u,int n){
for(auto x:adj[v]){
if(ded[x.fi] || x.fi == u)continue;
if(sub[x.fi] > n/2)return cen(x.fi,v,n);
}
return v;
}
vector<int>st,ed;
void dfs(int v,int u,int type,int ww){ //type 1 increasing,type 2 decreasing
if(type<=1)st.pb(v);
if(type!=1)ed.pb(v);
join[v] = max(join[u],ww);
reach[v] = min(reach[u],ww);
for(pii z:adj[v]){
int x = z.fi;
int w = z.se;
if(x==u || ded[x])continue;
if((!type || type ==1) && ww > w)dfs(x,v,1,w);
if((!type || type ==2) && ww < w)dfs(x,v,2,w);
}
}
void solve(int v){
get(v,0);
v = cen(v,0,sub[v]);
ded[v] = 1;
join[v] = 0;
reach[v] = 1e9;
for(auto z:adj[v]){
int x = z.fi;
int w = z.se;
if(ded[x])continue;
dfs(x,v,0,w);
}
//for a st node i,want number of ed nodes j st reach[j] > join[i] and join[j] <= current ime
//first ineq eliminate by sweep line
//second ineq can eliminate by [insert ds]
st.pb(v);
sort(all(st),[&](int i,int j){return join[i] > join[j];});
sort(all(ed),[&](int i,int j){return reach[i] > reach[j];});
int ptr = 0;
for(int i=0;i<sz(st);i++){
while(ptr<sz(ed) && reach[ed[ptr]] > join[st[i]]){
upd(join[ed[ptr]],1);
ptr++;
}
for(int tim : cq[st[i]]){
/*
for(int j=0;j<ptr;j++){
if(join[ed[j]] <= tim+1)ans[tim]++;
}*/
ans[tim]+=query(tim+1);
if(st[i]!=v && join[st[i]] <= tim+1)ans[tim]++;
}
}
for(int i=0;i<ptr;i++)upd(join[ed[i]],-1);
st.clear();
ed.clear();
for(auto z:adj[v])if(!ded[z.fi])solve(z.fi);
}
int main()
{
cin>>n>>k;
for(int i=0;i<n+k-1;i++){
cin>>c[i]>>a[i];
if(c[i]!='C')cin>>d[i];
if(c[i] == 'S'){
adj[a[i]].pb({d[i],i+1});
adj[d[i]].pb({a[i],i+1});
}
if(c[i]=='C')cq[a[i]].pb(i);
}
dfs0(1,0,0);
solve(1);
for(int i=0;i<n+k-1;i++){
if(c[i]=='C')cout<<ans[i]+1<<'\n';
else if(c[i]=='Q'){ //this solves for Q queries now for C queries
int v = a[i];
int u = d[i];
int m = lca(v,u),last = -1e9;
if(v!=m)last = val[v];
else if(u!=m)last = val[jump(u,dep[u]-dep[m]-1)];
bool ok= (last<=i);
if(asc[v] > dep[m] || dsc[u] > dep[m])ok = 0;
if(v!=m && u!= m){
v = jump(v,dep[v]-dep[m]-1);
u = jump(u,dep[u]-dep[m]-1);
if(val[u] > val[v])ok = 0;
}
if(ok)cout<<"yes"<<'\n';
else cout<<"no"<<'\n';
}
}
}
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