#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

char*mmap();
#define RD(v) int v=0;{int _c;while(_c=*rp++-48,_c>=0)v=v*10+_c;}

#define MAXN 200000
en[MAXN+1];
ei[MAXN+1];
eb[MAXN<<1];
uv[MAXN<<1];

c[100000];

void f(int i,int p,int d){
	c[i]=d;
	for(int k=0;k<en[i];++k){
		int j=eb[ei[i]+k];
		if(j!=p){
			f(j,i,d+1);
		}
	}
}

main(){
	char*rp=mmap(0l,1l<<28,1,2,0,0ll);
	RD(n);
	{
		int ne=n-1<<1;
		for(int j=0;j<ne;++j){
			RD(t);
			uv[j]=t;
			++en[uv[j]];
		}
	}
	{
		int s=0;
		for(int i=0;++i<=n;){
			ei[i]=s;
			s+=en[i];
			en[i]=0;
		}
	}
	{
		int ne=n-1<<1;
		for(int j=0;j<ne;++j){
			int i=uv[j];
			eb[ei[i]+en[i]++]=uv[j^1];
		}
	}
	int r=1;
	while(en[r]!=1)++r;
	f(r,r,0);
	int e=0;
	for(int i=r+1;i<=n;++i){
		if(en[i]==1){
			if(e==0){
				e=c[i];
			}else{
				if(c[i]!=e){
					write(1,"No",2);
					_exit(0);
				}
			}
		}
	}
	for(int i=0;i<n;++i){
		if(en[i]>2){
			if(c[i]*2!=e){
				write(1,"No",2);
				_exit(0);
			}
		}
	}
	write(1,"Yes",3);
	_exit(0);
}