use std::io::*;

fn dfs(v: usize, p: usize, g: &Vec<Vec<usize>>) -> usize {
    let mut res = 1;
    for &nv in g[v].iter() {
        if nv != p {
            res += dfs(nv, v, g);
        }
    }
    res
}

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<usize> = vec![0; n];
    for _ in 0..n - 1 {
        let a: usize = itr.next().unwrap().parse::<usize>().unwrap() - 1;
        let b: usize = itr.next().unwrap().parse::<usize>().unwrap() - 1;
        deg[a] += 1;
        deg[b] += 1;
        g[a].push(b);
        g[b].push(a);
    }
    let mut big = n;
    for i in 0..n {
        if deg[i] > 2 {
            if big != n {
                println!("No");
                return;
            }
            big = i;
        }
    }
    if big == n {
        println!("Yes")
    } else {
        let mut same = n;
        let mut ok = true;
        for &v in g[big].iter() {
            if same == n {
                same = dfs(v, big, &g);
            } else {
                ok &= same == dfs(v, big, &g);
            }
        }
        if ok {
            println!("Yes");
        } else {
            println!("No");
        }
    }
}