#include <bits/stdc++.h>
using namespace std;
#define int long long
#define double long double
#define f first
#define s second
const int N = 2e5 + 44;

vector < int > g[N];

void find() {
    int n;
    cin >> n;
    for (int i = 0; i < n; ++i) g[i].clear ();
    for (int i = 1; i < n; ++i) {
        int u, v;
        cin >> u >> v;
        g[v].push_back(u);
        g[u].push_back(v);
    }

    /*set < pair < int , int > > st;
    vector < int > final;
    for (int i = 0; i < n; ++i) {
        st.insert({g[i].size (), i});
    }
    queue < pair < int , int >
    while (!st.)*/
    vector<int> sz(N, 1);
    vector<int> used(N, 0);
    vector<int> deg(N, 0);
    priority_queue<pair<int, int>, vector<pair<int,int> >, greater<pair<int,int> > > q1;
    for(int i = 1; i <= n; i++) {
        deg[i] = g[i].size();
        if (g[i].size() == 1) {
            used[i] = 1;
            q1.push({1, i});
        }
    }
    while(q1.size() != 0) {
        pair<int,int> a = q1.top();
        q1.pop();
        deg[a.s]--;
        for(auto k:g[a.s]) {
            if (deg[k] != 0) {
                if (sz[k] < a.f) {
                    cout << "NO";
                    return;
                }
                sz[k] += a.f;
                deg[k]--;
                if (deg[k] == 1) {
                    q1.push({sz[k], k});
                }
            }
        }
    }
    cout << "YES";
}

int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int t = 1;
    while(t--) {
        find();
    }
    return 0;
}