#include <bits/stdc++.h>
#define int int64_t
using namespace std;
int N;
set<int> v[200010];
set<pair<int,int>> foglie[200010];
vector<int> dim(200010, 1);
signed main(){
    ios_base::sync_with_stdio();
    cin.tie(0);
    cin>>N;
    for(int i=0;i<N-1;i++){
        int a,b;
        cin>>a>>b;--a;--b;
        v[a].insert(b);
        v[b].insert(a);
    }
    queue<int> ok;
    for(int i=0;i<N;i++){
        if(v[i].size()==1){
            foglie[*v[i].begin()].insert({dim[i], i});
        }
    }
    for(int i=0;i<N;i++){
        if(foglie[i].size()==0)continue;
        if(foglie[i].begin()-> first<=dim[i])ok.push(foglie[i].begin()->second);
    }
    int tolti = 0;
    while(ok.size()){
        auto x = ok.front();
        ok.pop();
        if(v[x].size()==0)continue;
        tolti++;
        int par = *v[x].begin();
        v[x].clear();
        v[par].erase(x);
        dim[par]+=dim[x];
        foglie[par].erase({dim[x], x});

        if(foglie[par].begin()-> first<=dim[par])ok.push(foglie[par].begin()->second);

        if(v[par].size()==1){
            int q = *(v[par].begin());
            foglie[q].insert({dim[par], par});
            if(foglie[q].begin()-> first<=dim[q])ok.push(foglie[q].begin()->second);
        }
    }
    if(tolti>=N-2){
        cout<<"YES\n";
    }else{
        cout<<"NO\n";
    }
}