#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pi;
#define all(x) begin(x),end(x)
#define rep(i,a,b) for(int i=a;i<b;++i)
// #define sz(x) int(x.size())
int main() {
    cin.tie(NULL);
    cin.sync_with_stdio(false);
    int n; cin >> n;
    vvi adj(n);
    for(int i=0;i<n-1;++i) {
        int u,v; cin >> u >> v;
        --u,--v;
        adj[u].push_back(v);
        adj[v].push_back(u);

    }
    vi sz(n,1);
    auto dfs = [&](auto&& self, int at, int from) -> void {
        for(int to : adj[at]) if(to!=from) {
            self(self,to,at);
            sz[at]+=sz[to];
        }

    };
    dfs(dfs,0,-1);
    int centr=-1;
    
    int at=0,from=-1;
    while(true) {
        bool found=0;
        for(int to : adj[at]) if(to!=from) {
            if(sz[to]*2>=n) {
                from=at;
                at=to;
                found=1;
                break;
            }
        }
        if(!found) {
            centr=at;
            break;
        }
    }
    fill(all(sz),1);
    auto dfs2 = [&](auto&& self, int at, int from) -> void {
        vi s;
        for(int to : adj[at]) if(to!=from) {
            self(self,to,at);
            s.push_back(sz[to]);
        }
        sort(all(s));
        for(auto v : s) {
            if(sz[at]<v) {
                cout << "NO\n";
                exit(0);
            }
            sz[at]+=v;
        }

    };
    dfs2(dfs2,centr,-1);
    cout << "YES\n";

}