// -*- coding:utf-8-unix -*-
// #![feature(map_first_last)]
#![allow(dead_code)]
#![allow(unused_imports)]
#![allow(unused_macros)]
use std::collections::*;
use std::convert::*;
use std::convert::{From, Into};
use std::fmt::Debug;
use std::fs::File;
use std::io::prelude::*;
use std::io::*;
use std::marker::Copy;
use std::mem::*;
use std::ops::Bound::*;
use std::ops::{Add, Mul, Neg, Sub};
use std::str;
use std::vec;
use std::{cmp, process::Output};
use std::{cmp::Ordering, env::consts::DLL_PREFIX};
use std::{cmp::Ordering::*, f32::consts::PI};

const INF: i64 = 1223372036854775807;
const UINF: usize = INF as usize;
const FINF: f64 = 122337203685.0;
const INF128: i128 = 1223372036854775807000000000000;
const LINF: i64 = 2147483647;
// const MOD: i64 = 1000000007;
const MOD: i64 = 998244353;
const UMOD: usize = MOD as usize;
use std::cmp::*;
use std::collections::*;
use std::io::stdin;
use std::io::stdout;
use std::io::Write;

macro_rules! p {
    ($x:expr) => {
        println!("{}", $x);
    };
}

macro_rules! d {
    ($x:expr) => {
        dbg!($x);
    };
}

// use str::Chars;
#[allow(dead_code)]
fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

// #[allow(dead_code)]
// fn readi() -> (i64) {
//     let mut str = String::new();
//     let _ = stdin().read_line(&mut str).unwrap();
//     let mut iter = str.split_whitespace();
//     iter.next().unwrap().parse::<i64>().unwrap()
// }

#[allow(dead_code)]
fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}
#[allow(dead_code)]
fn read_vec2<T: std::str::FromStr>(n: u32) -> Vec<Vec<T>> {
    (0..n).map(|_| read_vec()).collect()
}

#[allow(dead_code)]
fn readii() -> (i64, i64) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
    )
}

fn readff() -> (f64, f64) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<f64>().unwrap(),
        iter.next().unwrap().parse::<f64>().unwrap(),
    )
}

#[allow(dead_code)]
fn readiii() -> (i64, i64, i64) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
    )
}
#[allow(dead_code)]
fn readuu() -> (usize, usize) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
    )
}

fn readcc() -> (char, char) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<char>().unwrap(),
        iter.next().unwrap().parse::<char>().unwrap(),
    )
}

#[allow(dead_code)]
fn readuuu() -> (usize, usize, usize) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
    )
}

#[allow(dead_code)]
fn readuuuu() -> (usize, usize, usize, usize) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
    )
}

fn readiiii() -> (i64, i64, i64, i64) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
    )
}

fn readin() -> (String, String) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        // iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<String>().unwrap(),
        iter.next().unwrap().parse::<String>().unwrap(),
    )
}

fn dfs(v: usize, graph: &Vec<Vec<(usize, usize)>>, used: &mut Vec<usize>, data: &mut Vec<usize>) {
    used[v] = 1;
    for i in graph[v].iter() {
        let nv = (*i).0;
        if used[nv] == 1 {
            continue;
        }
        data[nv] = data[v] + 1;
        dfs(nv, &graph, used, data);
    }
    return;
}
macro_rules! chmin {
    (base:expr, $(cmps:expr),+ $(,)*) => {{
        let cmp_min = min!($(cmps),+);
        if base > cmp_min {
            base = cmp_min;
            true
        } else {
            false
        }
    }};
}

macro_rules! chmax {
    (base:expr, $(cmps:expr),+ $(,)*) => {{
        let cmp_max = max!($(cmps),+);
        if base < cmp_max {
            base = cmp_max;
            true
        } else {
            false
        }
    }};
}

macro_rules! min {
    (a:expr $(,)*) => {{
        a
    }};
    (a:expr, b:expr $(,)*) => {{
        std::cmp::min(a, b)
    }};
    (a:expr, $(rest:expr),+ $(,)*) => {{
        std::cmp::min(a, min!($(rest),+))
    }};
}

macro_rules! max {
    (a:expr $(,)*) => {{
        a
    }};
    (a:expr, b:expr $(,)*) => {{
        std::cmp::max(a, b)
    }};
    (a:expr, $(rest:expr),+ $(,)*) => {{
        std::cmp::max(a, max!($(rest),+))
    }};
}

fn solve() {
    let n: usize = read();

    let mut graph = vec![vec![(0 as usize, 0 as usize); (0) as usize]; (n) as usize];
    for i in 0..n - 1 {
        let (mut a, mut b) = readuu();
        a -= 1;
        b -= 1;
        graph[a].push((b, 1));
        graph[b].push((a, 1));
    }

    // let mut x = 0 as usize;
    let mut f1 = true;
    let mut leaf = vec![0; 0];
    let mut r = 0 as usize;
    let mut mr = 0 as usize;
    let mut rr = vec![0; 0];
    for i in 0..n {
        if graph[i].len() == 1 {
            leaf.push(i);
        }
        if graph[i].len() > 2 {
            f1 = false;
        }
        if mr < graph[i].len() {
            mr = graph[i].len();
            r = i;
            rr = vec![i];
        } else if mr == graph[i].len() {
            rr.push(i);
        }
        // d!(graph[i].len());
    }

    if f1 {
        println!("{}", "Yes");
        return;
    }
    let mut flg = true;
    for i in 0..n {
        if graph[i].len() > 2 && graph[i].len() != mr && graph[i].len() > 2 {
            flg = false;
        }
    }

    for l1 in rr {
        // let mut l1 = r;
        let mut used = vec![0; n];
        let mut data = vec![0; n];
        dfs(l1, &graph, &mut used, &mut data);
        // let mut  = 0 as usize;
        // let mut = 0 as usize;
        let mut d = vec![0; 0];
        for i in 0..leaf.len() {
            let mut l = leaf[i];
            d.push(data[l]);
        }

        for i in 0..d.len() - 1 {
            if d[i] != d[i + 1] {
                flg = false;
            }
        }
    }
    // d!(data);
    if flg {
        println!("Yes");
    } else {
        println!("No");
    }
    return;
}

fn main() {
    solve()
}