use std::io::*;

fn main() {
    let mut s: String = String::new();
    std::io::stdin().read_to_string(&mut s).ok();
    let mut itr = s.trim().split_whitespace();
    let n: usize = itr.next().unwrap().parse().unwrap();
    let mut g: Vec<Vec<usize>> = vec![Vec::new(); n];
    let mut deg = vec![0; n];
    for _ in 0..n - 1 {
        let a = itr.next().unwrap().parse::<usize>().unwrap() - 1;
        let b = itr.next().unwrap().parse::<usize>().unwrap() - 1;
        g[a].push(b);
        deg[b] += 1;
    }

    let mut start = 0;
    for i in 0..n {
        if deg[i] == 0 {
            start = i;
        }
    }

    let mut q = std::collections::VecDeque::new();
    let mut dist = vec![0; n];
    q.push_back(start);

    let mut ans = 0;
    while let Some(v) = q.pop_front() {
        ans += dist[v] * (dist[v] + 1) / 2;
        for &nv in g[v].iter() {
            dist[nv] = dist[v] + 1;
            q.push_back(nv);
        }
    }
    println!("{}", ans);
}