#include <bits/stdc++.h>

using namespace std;
using ll = long long;

vector<int> bfs(vector<vector<int>> &E, int start){

    int N = E.size();
    int from, to;
    queue<int> que;
    vector<int> dist(N, 1e9);

    dist[start] = 0;
    que.push(start);

    while(!que.empty()){
        from = que.front();
        que.pop();
        for (auto to : E[from]){
            if (dist[to] != 1e9) continue;
            dist[to] = dist[from] + 1;
            que.push(to);
        }
    }

    return dist;
}

int main(){

    int N, a, b, cnt=0, cnt2=0, d, e;
    cin >> N;
    vector<int> deg(N);
    vector<vector<int>> E(N);
    for (int i=0; i<N-1; i++){
        cin >> a >> b; a--; b--;
        deg[a]++;
        deg[b]++;
        E[a].push_back(b);
        E[b].push_back(a);
    }

    for (int i=0; i<N; i++){
        if (deg[i] == 1) cnt++;
        else if (deg[i] >= 3){
            cnt2++;
            d = deg[i];
            e = i;
        }
    }

    if (cnt == 2){
        cout << "Yes" << endl;
        return 0;
    }
    else if (cnt2 > 1){
        cout << "No" << endl;
        return 0;
    }

    vector<int> dist = bfs(E, e);
    vector<int> v;
    for (int i=0; i<N; i++){
        if (deg[i] == 1) v.push_back(dist[i]);
    }

    for (int i=0; i<v.size(); i++){
        if (v[i] != v[0]){
            cout << "No" << endl;
            return 0;
        }
    }

    cout << (cnt == d ? "Yes" : "No") << endl;

    return 0;
}