#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++)
#define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++)
#define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--)
#define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((ll)(x).size())
#define len(x) ((ll)(x).length())
#define endl "\n"

vector<vector<ll>> g, rev;
ll ans = 0;

ll dfs(ll v, ll p = 1) {
    ll cnt = 0;
    for(auto &x : g[v]) {
        cnt += dfs(x, p + 1);
    }
    ans += p * cnt;
    return cnt + 1;
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    ll n;
    cin >> n;
    g.resize(n);
    rev.resize(n);
    rep(i, n - 1) {
        ll a, b;
        cin >> a >> b;
        a--; b--;
        g[a].push_back(b);
        rev[b].push_back(a);
    }
    rep(i, n) {
        if (sz(rev[i]) == 0) dfs(i);
    }
    cout << ans << endl;
    return 0;
}