8.Subtree Queries using DFS

 #include <bits/stdc++.h>

#include <ext/pb_ds/assoc_container.hpp>

#include <ext/pb_ds/tree_policy.hpp>

using namespace std;

using namespace __gnu_pbds;

template <class type1>

#define ll long long int

#define endl "\n"

#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>

using ordered_multiset = tree <type1, null_type, less_equal <type1>, rb_tree_tag, tree_order_statistics_node_update>;

 //ordered_multiset <ll> kek;(declaration for multiorder set)

// ordered_set o_set;(declaration)

//kek.order_of_key(i);(strictly less then i for multi order set)

//o_set.order_of_key(5) ;(strictly less then i for multi order set)

#define yes cout << "YES\n"

#define no cout << "NO\n"

#define mod 1000000007

ll POW(ll a,ll b)

{   ll ans=1;

   while(b>0)

   {   if(b%2)ans=(ans*a)%mod;

       b/=2;

       a=(a*a)%mod;

   }

   return ans;

}

vector<ll>adj[500000];

ll cnt[500000];

ll sum[500000];

ll dfs(ll node ,ll par=0)

{

     if(node%2==0)

     {

         cnt[node]+=1;

     }

     sum[node]+=node;

     for(auto u:adj[node])

     {

         if(par==u)continue;

          dfs(u,node);

          sum[node]+=sum[u];

          cnt[node]+=cnt[u];

     }

}

int main()

{

    ios_base::sync_with_stdio(0);

    cin.tie(0);

    cout.tie(0);

   

     ll n;

     cin>>n;

     ll i;

     for(i=0;i<n-1;i++)

     {

         ll u,v;

         cin>>u>>v;

         adj[u].push_back(v);

         adj[v].push_back(u);

     }

 

     dfs(1);

     for(i=1;i<=n;i++)

     {

        cout<<sum[i]<<" "<<cnt[i]<<endl;

     }

    return 0;

}