#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;
using P=pair<ll,ll>;

void IO(){
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
}

void dfs(ll now,set<ll> &seen,ll depth,vector<ll> &used,vector<vector<ll>> &G){
  for(ll next:G[now]){
    if(seen.find(next)==seen.end()){
      if(depth<=2){
        seen.insert(next);
        used.push_back(next);
        dfs(next,seen,depth+1,used,G);
        seen.erase(next);
      }
    }
  }
}

int main(){
  IO();
  ll n;
  cin>>n;
  vector<vector<ll>> G(n);
  for(ll i=0;i<n-1;i++){
    ll u,v;
    cin>>u>>v;
    u--;
    v--;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  set<P> st;
  for(ll i=0;i<n;i++){
    set<ll> seen;
    seen.insert(i);
    vector<ll> used;
    dfs(i,seen,0,used,G);
    for(ll u:used){
      st.insert(P(i,u));
      st.insert(P(u,i));
    }
  }
  cout<<st.size()/2<<endl;
}