#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<long long> VL;
typedef vector<vector<long long>> VVL;
typedef pair<int,int> Pair;
typedef tuple<int,int,int> tpl;

#define ALL(a)  (a).begin(),(a).end()
#define SORT(c) sort((c).begin(),(c).end())
#define REVERSE(c) reverse((c).begin(),(c).end())
#define EXIST(m,v) (m).find((v)) != (m).end()
#define LB(a,x) lower_bound((a).begin(), (a).end(), x) - (a).begin()
#define UB(a,x) upper_bound((a).begin(), (a).end(), x) - (a).begin()

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define RFOR(i,a,b) for(int i=(a)-1;i>=(b);--i)
#define RREP(i,n) RFOR(i,n,0)

#define en "\n"

constexpr double EPS = 1e-9;
constexpr double PI  = 3.1415926535897932;
constexpr int INF = 2147483647;
constexpr long long LINF = 1LL<<60;
constexpr long long MOD = 1000000007; // 998244353;

template<class T> inline bool chmax(T& a, T b){if(a<b){a=b;return true;}return false;}
template<class T> inline bool chmin(T& a, T b){if(a>b){a=b;return true;}return false;}

bool is_path(VI& deg){
    for(int x : deg){
        if(x>2) return false;
    }
    return true;
}

VVI edge;
VI n_leaves, vis, depth;

void dfs(int v, int d){
    vis[v] = 1;
    depth[v] = d;
    for(int to : edge[v]){
        if(vis[to]) continue;
        n_leaves[v]++;
        dfs(to, d+1);
    }
    return;
}

void Main(){
    int N, mx=0, root=-1; cin >> N;
    VI deg(N,0); edge.resize(N);
    REP(i,N-1){
        int a,b; cin >> a >> b; a--; b--;
        edge[a].push_back(b); edge[b].push_back(a);
        deg[a]++; deg[b]++;
        if(chmax(mx, deg[a])) root = a;
        if(chmax(mx, deg[b])) root = b;
    }

    if(is_path(deg)){
        cout << "Yes" << en;
        return;
    }

    n_leaves.resize(N,0); vis.resize(N,0); depth.resize(N,0);
    dfs(root,0);

    VI v;
    REP(i,N){
        if(i == root) continue;
        if(n_leaves[i]>1){
            cout << "No" << en;
            return;
        }
        if(n_leaves[i]==0) v.push_back(depth[i]);
    }

    int sz = v.size();
    REP(i,sz-1){
        if(v[i] != v[i+1]){
            cout << "No" << en;
            return;
        }
    }
    cout << "Yes" << en;
    return;
}

int main(void){
    cin.tie(0);cout.tie(0);ios_base::sync_with_stdio(0);cout<<fixed<<setprecision(15);
    int t=1; //cin>>t;
    REP(_,t) Main();
    return 0;
}