/**
*    author:  shu8Cream
*    created: 13.03.2021 11:04:54
**/

#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for (int i=0; i<(n); i++)
#define all(x) (x).begin(), (x).end()
using ll = long long;
using P = pair<int,int>;
using vi = vector<int>;
using vvi = vector<vi>;

int n;
vi to[200005];
vi dist;

void dfs(int v, int p=-1){
    for(auto nv : to[v]){
        //if(dist[nv]!=-1) continue;
        if(nv == p) continue;
        dist[nv]=dist[v]+1;
        dfs(nv,v);
    }
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cin >> n;
    rep(i,n-1){
        int a,b;
        cin >> a >> b;
        a--; b--;
        to[a].push_back(b);
        to[b].push_back(a);
    }
    dist.resize(n);
    rep(i,n){
        if(to[i].size()==1){
            dist[i]=0;
            dfs(i);
            break;
        }
    }
    set<int> s;
    rep(i,n){
        if(dist[i] && to[i].size()==1) s.insert(dist[i]);
    }
    if(s.size()==1) cout << "Yes" << endl;
    else cout << "No" << endl;
}