供養2
//#define _GLIBCXX_DEBUG

//#pragma GCC target("avx2")
//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")

#include<bits/stdc++.h>
using namespace std;


#ifdef LOCAL
#include <debug_print.hpp>
#define OUT(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#define OUT(...) (static_cast<void>(0))
#endif

#define endl '\n'
#define lfs cout<<fixed<<setprecision(15)
#define ALL(a)  (a).begin(),(a).end()
#define ALLR(a)  (a).rbegin(),(a).rend()
#define UNIQUE(a) (a).erase(unique((a).begin(),(a).end()),(a).end())
#define spa << " " <<
#define fi first
#define se second
#define MP make_pair
#define MT make_tuple
#define PB push_back
#define EB emplace_back
#define rep(i,n,m) for(ll i = (n); i < (ll)(m); i++)
#define rrep(i,n,m) for(ll i = (ll)(m) - 1; i >= (ll)(n); i--)
using ll = long long;
using ld = long double;
const ll MOD1 = 1e9+7;
const ll MOD9 = 998244353;
const ll INF = 1e18;
using P = pair<ll, ll>;
template<typename T> using PQ = priority_queue<T>;
template<typename T> using QP = priority_queue<T,vector<T>,greater<T>>;
template<typename T1, typename T2>bool chmin(T1 &a,T2 b){if(a>b){a=b;return true;}else return false;}
template<typename T1, typename T2>bool chmax(T1 &a,T2 b){if(a<b){a=b;return true;}else return false;}
ll median(ll a,ll b, ll c){return a+b+c-max({a,b,c})-min({a,b,c});}
void ans1(bool x){if(x) cout<<"Yes"<<endl;else cout<<"No"<<endl;}
void ans2(bool x){if(x) cout<<"YES"<<endl;else cout<<"NO"<<endl;}
void ans3(bool x){if(x) cout<<"Yay!"<<endl;else cout<<":("<<endl;}
template<typename T1,typename T2>void ans(bool x,T1 y,T2 z){if(x)cout<<y<<endl;else cout<<z<<endl;}  
template<typename T1,typename T2,typename T3>void anss(T1 x,T2 y,T3 z){ans(x!=y,x,z);};  
template<typename T>void debug(const T &v,ll h,ll w,string sv=" "){for(ll i=0;i<h;i++){cout<<v[i][0];for(ll j=1;j<w;j++)cout<<sv<<v[i][j];cout<<endl;}};
template<typename T>void debug(const T &v,ll n,string sv=" "){if(n!=0)cout<<v[0];for(ll i=1;i<n;i++)cout<<sv<<v[i];cout<<endl;};
template<typename T>void debug(const vector<T>&v){debug(v,v.size());}
template<typename T>void debug(const vector<vector<T>>&v){for(auto &vv:v)debug(vv,vv.size());}
template<typename T>void debug(stack<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(queue<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(deque<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop_front();}cout<<endl;}
template<typename T>void debug(PQ<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(QP<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(const set<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;}
template<typename T>void debug(const multiset<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;}
template<typename T,size_t size>void debug(const array<T, size> &a){for(auto z:a)cout<<z<<" ";cout<<endl;}
template<typename T,typename V>void debug(const map<T,V>&v){for(auto z:v)cout<<"["<<z.first<<"]="<<z.second<<",";cout<<endl;}
template<typename T>vector<vector<T>>vec(ll x, ll y, T w){vector<vector<T>>v(x,vector<T>(y,w));return v;}
vector<ll>dx={1,-1,0,0,1,1,-1,-1};vector<ll>dy={0,0,1,-1,1,-1,1,-1};
template<typename T>vector<T> make_v(size_t a,T b){return vector<T>(a,b);}
template<typename... Ts>auto make_v(size_t a,Ts... ts){return vector<decltype(make_v(ts...))>(a,make_v(ts...));}
template<typename T1, typename T2>ostream &operator<<(ostream &os, const pair<T1, T2>&p){return os << "(" << p.first << "," << p.second << ")";}
template<typename T>ostream &operator<<(ostream &os, const vector<T> &v){os<<"[";for(auto &z:v)os << z << ",";os<<"]"; return os;}
template<typename T>void rearrange(vector<int>&ord, vector<T>&v){
  auto tmp = v;
  for(int i=0;i<tmp.size();i++)v[i] = tmp[ord[i]];
}
template<typename Head, typename... Tail>void rearrange(vector<int>&ord,Head&& head, Tail&&... tail){
  rearrange(ord, head);
  rearrange(ord, tail...);
}
template<typename T> vector<int> ascend(const vector<T>&v){
  vector<int>ord(v.size());iota(ord.begin(),ord.end(),0);
  sort(ord.begin(),ord.end(),[&](int i,int j){return make_pair(v[i],i)<make_pair(v[j],j);});
  return ord;
}
template<typename T> vector<int> descend(const vector<T>&v){
  vector<int>ord(v.size());iota(ord.begin(),ord.end(),0);
  sort(ord.begin(),ord.end(),[&](int i,int j){return make_pair(v[i],-i)>make_pair(v[j],-j);});
  return ord;
}
template<typename T> vector<T> inv_perm(const vector<T>&ord){
  vector<T>inv(ord.size());
  for(int i=0;i<ord.size();i++)inv[ord[i]] = i;
  return inv;
}
ll FLOOR(ll n,ll div){assert(div>0);return n>=0?n/div:(n-div+1)/div;}
ll CEIL(ll n,ll div){assert(div>0);return n>=0?(n+div-1)/div:n/div;}
ll digitsum(ll n){ll ret=0;while(n){ret+=n%10;n/=10;}return ret;}
ll modulo(ll n,ll d){return (n%d+d)%d;};
template<typename T>T min(const vector<T>&v){return *min_element(v.begin(),v.end());}
template<typename T>T max(const vector<T>&v){return *max_element(v.begin(),v.end());}
template<typename T>T acc(const vector<T>&v){return accumulate(v.begin(),v.end(),T(0));};
template<typename T>T reverse(const T &v){return T(v.rbegin(),v.rend());};
//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());
int popcount(ll x){return __builtin_popcountll(x);};
int poplow(ll x){return __builtin_ctzll(x);};
int pophigh(ll x){return 63 - __builtin_clzll(x);};
template<typename T>T poll(queue<T> &q){auto ret=q.front();q.pop();return ret;};
template<typename T>T poll(priority_queue<T> &q){auto ret=q.top();q.pop();return ret;};
template<typename T>T poll(QP<T> &q){auto ret=q.top();q.pop();return ret;};
template<typename T>T poll(stack<T> &s){auto ret=s.top();s.pop();return ret;};
ll MULT(ll x,ll y){if(LLONG_MAX/x<=y)return LLONG_MAX;return x*y;}
ll POW2(ll x, ll k){ll ret=1,mul=x;while(k){if(mul==LLONG_MAX)return LLONG_MAX;if(k&1)ret=MULT(ret,mul);mul=MULT(mul,mul);k>>=1;}return ret;}
ll POW(ll x, ll k){ll ret=1;for(int i=0;i<k;i++){if(LLONG_MAX/x<=ret)return LLONG_MAX;ret*=x;}return ret;}
std::ostream &operator<<(std::ostream &dest, __int128_t value) {
  std::ostream::sentry s(dest);
  if (s) {
    __uint128_t tmp = value < 0 ? -value : value;
    char buffer[128];
    char *d = std::end(buffer);
    do {
      --d;
      *d = "0123456789"[tmp % 10];
      tmp /= 10;
    } while (tmp != 0);
    if (value < 0) {
      --d;
      *d = '-';
    }
    int len = std::end(buffer) - d;
    if (dest.rdbuf()->sputn(d, len) != len) {
      dest.setstate(std::ios_base::badbit);
    }
  }
  return dest;
}
namespace converter{
  int dict[500];
  const string lower="abcdefghijklmnopqrstuvwxyz";
  const string upper="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  const string digit="0123456789";
  const string digit1="123456789";
  void regi_str(const string &t){
    for(int i=0;i<t.size();i++){
      dict[t[i]]=i;
    }
  }
  void regi_int(const string &t){
    for(int i=0;i<t.size();i++){
      dict[i]=t[i];
    }
  }
  vector<int>to_int(const string &s,const string &t){
    regi_str(t);
    vector<int>ret(s.size());
    for(int i=0;i<s.size();i++){
      ret[i]=dict[s[i]];
    }
    return ret;
  }
  vector<int>to_int(const string &s){
    auto t=s;
    sort(t.begin(),t.end());
    t.erase(unique(t.begin(),t.end()),t.end());
    return to_int(s,t);
  }
  
  vector<vector<int>>to_int(const vector<string>&s,const string &t){
    regi_str(t);
    vector<vector<int>>ret(s.size(),vector<int>(s[0].size()));
    for(int i=0;i<s.size();i++){
      for(int j=0;j<s[0].size();j++){
        ret[i][j]=dict[s[i][j]];
      }
    }
    return ret;
  }
  vector<vector<int>>to_int(const vector<string>&s){
    string t;
    for(int i=0;i<s.size();i++){
      t+=s[i];
    }
    sort(t.begin(),t.end());t.erase(unique(t.begin(),t.end()),t.end());
    return to_int(s,t);
  }
  string to_str(const vector<int>&s,const string &t){
    regi_int(t);
    string ret;
    for(auto z:s)ret+=dict[z];
    return ret;
  }
  vector<string> to_str(const vector<vector<int>>&s,const string &t){
    regi_int(t);
    vector<string>ret(s.size());
    for(int i=0;i<s.size();i++){
      for(auto z:s[i])ret[i]+=dict[z];
    }
    return ret;
  }
}
template< typename T = int >
struct edge {
  int to;
  T cost;
  int id;
  edge():to(-1),id(-1){};
  edge(int to, T cost = 1, int id = -1):to(to), cost(cost), id(id){}
  operator int() const { return to; }
};

template<typename T>
using Graph = vector<vector<edge<T>>>;
template<typename T>
Graph<T>revgraph(const Graph<T> &g){
  Graph<T>ret(g.size());
  for(int i=0;i<g.size();i++){
    for(auto e:g[i]){
      int to = e.to;
      e.to = i;
      ret[to].push_back(e);
    }
  }
  return ret;
}
template<typename T>
Graph<T> readGraph(int n,int m,int indexed=1,bool directed=false,bool weighted=false){
  Graph<T> ret(n);
  for(int es = 0; es < m; es++){
    int u,v;
    T w=1;
    cin>>u>>v;u-=indexed,v-=indexed;
    if(weighted)cin>>w;
    ret[u].emplace_back(v,w,es);
    if(!directed)ret[v].emplace_back(u,w,es);
  }
  return ret;
}
template<typename T>
Graph<T> readParent(int n,int indexed=1,bool directed=true){
  Graph<T>ret(n);
  for(int i=1;i<n;i++){
    int p;cin>>p;
    p-=indexed;
    ret[p].emplace_back(i);
    if(!directed)ret[i].emplace_back(p);
  }
  return ret;
}
struct UnionFind {
  vector<ll> data;
  ll num;
  UnionFind(ll size) : data(size, -1) ,num(size){ }
  bool unite(int x, int y) {
    x = root(x); y = root(y);
    if (x != y) {
      if (data[y] < data[x]) swap(x, y);
      data[x] += data[y]; data[y] = x;
	  num--;
    }
    return x != y;
  }
  bool find(int x, int y) {
    return root(x) == root(y);
  }
  int root(int x) {
    return data[x] < 0 ? x : data[x] = root(data[x]);
  }
  ll size(int x) {
    return -data[root(x)];
  }
  vector<vector<int>>groups(){
    vector<vector<int>>ret(data.size());
    for(int i=0;i<data.size();i++){
      ret[root(i)].push_back(i);
    }
    return ret;
  }
  void print(){
    auto tmp=groups();
    for(int i=0;i<data.size();i++){
      if(!tmp[i].empty()){
        for(auto z:tmp[i])cout<<z<<",";
        cout<<endl;
      }
    }
  }
};
template<typename T>
vector<int>nibu_graph(const Graph<T>&g){
  int n=g.size();
  vector<int>t(n,-1);
  queue<int>que;
  for(ll i=0;i<n;i++){
    if(t[i]!=-1)continue;
    que.push(i);
    t[i]=0;
    while(!que.empty()){
      auto p=que.front();que.pop();
      for(auto e:g[p]){
        if(t[e.to]==-1){
          que.push(e.to);
          t[e.to]=t[p]^e.cost;
        }
        else if(t[p]!=(t[e.to]^e.cost))return vector<int>();
      }
    }
  }
  return t;
}
template<typename T>
vector<pair<bool,vector<vector<int>>>>nibu_graph_con(const Graph<T>&g){
  int n=g.size();
  vector<pair<bool,vector<vector<int>>>>v;
  vector<int>t(n,-1);
  queue<int>que;
  for(ll i=0;i<n;i++){
    if(t[i]!=-1)continue;
    que.emplace(i);
    v.emplace_back(true,vector<vector<int>>(2));
    t[i]=0;
    while(!que.empty()){
      auto p=que.front();que.pop();
      v.back().second[t[p]].push_back(p);
      for(auto e:g[p]){
        if(t[e.to]==-1){
          que.push(e.to);
          t[e.to]=t[p]^e.cost;
        }
        else if(t[p]!=(t[e.to]^e.cost))v.back().first=false;
      }
    }
  }
  return v;
}
void solve(){
	ll res=0,buf=0;
  bool judge = true;

  int n,q;cin>>n>>q;
  UnionFind uf(n);
  auto gg=readGraph<int>(n,n-1);
  vector<int>leaf(n,-1),ch(n,-1),ch2(n,-1),par(n),in(n);
  {
    int time;
    auto dfs=[&](auto &&f,int i,int pa)->void {
      par[i]=pa;
      in[i]=time++;
      if(gg[i].size()==1&&pa!=-1){
        leaf[i]=gg[i][0];
        if(ch[gg[i][0]]==-1)ch[gg[i][0]]=i;
        else{
          if(ch2[gg[i][0]]==-1)ch2[gg[i][0]]=i;
          uf.unite(i,ch[gg[i][0]]);
        }
      }
      for(auto to:gg[i]){
        if(pa==to)continue;
        f(f,to,i);
      }
    };
    dfs(dfs,0,-1);
  }
  rep(i,0,n){
    if(ch2[i]==-1&&ch[i]!=-1)ch2[i]=ch[i];
  }
  auto c=nibu_graph(gg);
  vector<vector<int>>g(n);
  rep(i,0,n){
    for(auto to:gg[i]){
      if(leaf[to]!=-1&&to!=ch[i]&&to!=ch2[i])continue;
      if(in[i]>in[to])continue;
      g[i].PB(to);
      g[to].PB(i);
    }
  }
  q++;
  vector<int>type(q),w(q,-1);
  vector<int>xt(q+1);
  vector<int>tt;
  rep(i,0,q){
    if(i<q-1)cin>>type[i];
    else type[i]=2;
    if(type[i]!=2){
      if(i<q-1)cin>>w[i],w[i]--;
    }
    else{
      xt[i]++;
      tt.PB(i);
    }
  }
  rep(i,0,q)xt[i+1]+=xt[i];
  auto imos=vec(2,q+1,0);
  rep(pt,0,2){
    //(xt[t]+c[v])%2==ptを処理
    // time, is_mark
    vector<vector<pair<int,int>>>event(n);
    map<int,pair<int,int>>mp;
    vector<vector<pair<int,int>>>lt(n);
    rep(i,0,n){
      event[i].EB(-1,0);
    }
    OUT(leaf,ch,ch2,g);
    rep(i,0,q){
      if(type[i]==2){
        if(i==q-1)continue;
        map<int,int>mppd;
        for(auto [v,tmp]:mp){
          auto [pt,ty]=tmp;
          if(ty==0&&par[v]!=-1)mppd[par[v]]++;
          if(ty==0&&ch[v]!=-1){
            event[ch[v]].EB(i,0);
            if(ch[v]!=ch2[v])event[ch2[v]].EB(i,0);
          }
        }
        for(auto [v,deg]:mppd){
          if(deg+1==gg[v].size()&&mp.count(v)&&mp[v].se==0){
            //OUT(deg,v,gg[v]);
            event[v].EB(i,0);
          }
        }
        mp.clear();
      }
      else{
        if((xt[i]+c[w[i]])%2!=pt)continue;
        int v=w[i],ty=type[i];
        if(leaf[v]==-1){
          event[v].EB(i,ty);
        }
        else{
          int vv=par[v];
          event[ch[vv]].EB(i,ty);
          lt[ch2[vv]].EB(i,ty);
        }
        mp[w[i]]=MP(i,type[i]);
      }
    }
    OUT(event);
    vector<vector<int>>dt(n);
    rep(i,0,n)dt[i].assign(event[i].size(),q);
    priority_queue<pair<int,pair<int,int>>>pq;
    rep(i,0,n){
      rep(j,0,event[i].size()){
        if(event[i][j].se==1){
          pq.emplace(event[i][j].fi,MP(i,j));
          dt[i][j]=event[i][j].fi;
        }
      }
    }
    //OUT(pq);
    while(!pq.empty()){
      auto [gd,ppp]=poll(pq);
      auto [i,j]=ppp;
      if(dt[i][j]!=gd)continue;
      OUT(i,j,event[i][j],gd);
      int suf=q;
      if(j+1<event[i].size())suf=event[i][j+1].se;
      if(suf==event[i][j].fi)continue;
      if(leaf[i]==-1){
        //OUT(i,j,gd,suf);
        imos[xt[gd]&1][gd]++;
        imos[xt[gd]&1][suf]--;
      }
      else if(ch2[par[i]]==i){
        map<int,pair<int,int>>prev;
        int idx=lower_bound(ALL(lt[i]),MP(event[i][j].se,-1))-lt[i].begin();
        if(idx<0)idx++;
        while(idx<lt[i].size()){
          auto [nt,nv]=lt[i][idx];
          if(nt>=suf)break;
          idx++;
          auto [pt,ty]=prev[nv];
          if(ty==1){
            imos[xt[gd]&1][pt]++;
            imos[xt[gd]&1][nt]--;
          }
          prev[nv]=MP(pt,ty);
        }
        for(auto [ppp,tmp]:prev){
          auto [pt,ty]=tmp;
          if(ty==1){
            imos[xt[gd]&1][pt]++;
            imos[xt[gd]&1][suf]--;
          }
        }
        imos[xt[gd]&1][gd]+=uf.size(i)-prev.size();
        imos[xt[gd]&1][suf]-=uf.size(i)-prev.size();
      }
      if(gd==q)continue;
      //OUT(gd,q);
      for(auto to:g[i]){
        int nd=tt[xt[gd]];
        OUT(nd,gd,xt[gd]);
        if(nd>=q-1)continue;
        int idx=--lower_bound(ALL(event[to]),MP(nd,-1))-event[to].begin();
        OUT(idx,nd,dt[to][idx]);
        if(chmin(dt[to][idx],nd)){
          pq.emplace(nd,MP(to,idx));
        }
      }
    }
    OUT(dt);
  }
  rep(i,0,2){
    rep(j,0,q)imos[i][j+1]+=imos[i][j];
  }
  vector<int>ret;
  rep(i,0,q-1)ret.PB(imos[xt[i]%2][i]);
  debug(ret);
}

int main(){
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  ll res=0,buf=0;
  bool judge = true;
  int T = 1;
  //cin>>T;
  while(T--){
    solve();
  }
  return 0;
}

answer.code:1:1: error: ‘供養2’ does not name a type
    1 | 供養2
      | ^~~~~
In file included from /usr/include/c++/11/cmath:43,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:8:
/usr/include/c++/11/ext/type_traits.h:162:35: error: ‘bool __gnu_cxx::__is_null_pointer’ redeclared as different kind of entity
  162 |   __is_null_pointer(std::nullptr_t)
      |                                   ^
/usr/include/c++/11/ext/type_traits.h:157:5: note: previous declaration ‘template<class _Type> bool __gnu_cxx::__is_null_pointer(_Type)’
  157 |     __is_null_pointer(_Type)
      |     ^~~~~~~~~~~~~~~~~
/usr/include/c++/11/ext/type_traits.h:162:26: error: ‘nullptr_t’ is not a member of ‘std’
  162 |   __is_null_pointer(std::nullptr_t)
      |                          ^~~~~~~~~
In file included from /usr/include/c++/11/bits/move.h:57,
                 from /usr/include/c++/11/bits/stl_pair.h:59,
                 from /usr/include/c++/11/bits/stl_algobase.h:64,
                 from /usr/include/c++/11/bits/specfun.h:45,
                 from /usr/include/c++/11/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:8:
/usr/include/c++/11/type_traits:405:26: error: ‘std::size_t’ has not been declared
  405 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/11/type_traits:406:25: error: ‘_Size’ was not declared in this scope
  406 |     struct is_array<_Tp[_Size]>
      |                         ^~~~~
/usr/include/c++/11/type_traits:406:31: error: template argument 1 is invalid
  406 |     struct is_array<_Tp[_Size]>
      |                               ^
/usr/include/c++/11/type_traits:511:42: error: ‘nullptr_t’ is not a member of ‘std’
  511 |     struct __is_null_pointer_helper<std::nullptr_t>
      |                                          ^~~~~~~~~
/usr/include/c++/11/type_traits:511:51: error: template argument 1 is invalid
  511 |     struct __is_null_pointer_helper<std::nullptr_t>
      |                                                   ^
/usr/include/c++/11/type_traits:1311:37: error: ‘size_t’ is not a member of ‘std’; did you mean ‘size_t’?
 1311 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/11/bits/std_abs.h:38,
                 from /usr/include/c++/11/cmath:47,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:8:
/usr/lib/gcc/x86_64-linux-gnu/11/include/stddef.h:209:23: note: ‘size_t’ declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/11/bits/move.h:57,
                 from /usr/include/c++/11/bits/stl_pair.h:59,
                 from /usr/include/c++/11/bits/stl_algobase.h:64,
                 from /usr/include/c++/11/bits/specfun.h:45,
                 from /usr/include/c++/11/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:8:
/usr/include/c++/11/type_traits:1311:57: error: template argument 1 is invalid
 1311 |     : public integral_constant<std::size_t, alignof(_Tp)>
      |                                                         ^
/usr/include/c++/11/type_traits:1320:37: error: ‘size_t’ is not a member of ‘std’; did you mean ‘size_t’?
 1320 |     : public integral_constant<std::size_t, 0> { };
      |                                     ^~~~~~
In file included from /usr/include/stdlib.h:31,
                 from /usr/include/c++/11/bits/std_abs.h:38,
                 from /usr/include/c++/11/cmath:47,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:8:
/usr/lib/gcc/x86_64-linux-gnu/11/include/stddef.h:209:23: note: ‘size_t’ declared here
  209 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
In file included from /usr/include/c++/11/bits/move.h:57,
                 from /usr/include/c++/11/bits/stl_pair.h:59,
                 from /usr/include/c++/11/bits/stl_algobase.h:64,
                 from /usr/include/c++/11/bits/specfun.h:45,
                 from /usr/include/c++/11/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:8:
/usr/include/c++/11/type_traits:1320:46: error: template argument 1 is invalid
 1320 |     : public integral_constant<std::size_t, 0> { };
      |                                              ^
/usr/include/c++/11/type_traits:1322:26: error: ‘std::size_t’ has not been declared
 1322 |   template<typename _Tp, std::size_t _Size>
      |                          ^~~
/usr/include/c++/11/type_traits:1323:21: error: ‘_Size’ was not declared in this scope
 1323 |     struct rank<_Tp[_Size]>
     ...