/*                        _
                       _oo0oo_
                      o8888888o
                      88" . "88
                      (| -_- |)
                      0\  =  /0
                   ____/`---'\____
                  /  \\|     |//  \
                 / \\||| /:\ |||// \
                / _||||| -:- |||||- \
               |   | \\\ \-/ /// |   |
               | \_|  ''\---/''  |_/ |
               \  .-\__  '-'  ___/-. /
            ____'. .'  /--.--\  `. .'_____
          /"" '<  `.___\_<|>_/___.' >' "" \
         | | :  `- \`.;`\ _ /`;.`/ - ` : | |
         \  \ `_.   \_ __\ /__ _/   .-` /  /
          `-.____`.___ \_____/___.-`___.-'

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ash_1_e                     IIT Patna
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

#include<bits/stdc++.h>
using namespace std;

#define ll long long int
#define IOS ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define FRE freopen("input.txt","r",stdin); freopen("output.txt","w",stdout);
#define f(i,n) for(ll i=0;i<n;i++)
#define fa(i,a,n) for(ll i=a;a<n?i<n:i>n;a<n?i+=1:i-=1)
#define pb push_back
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define clr(x) memset(x, 0, sizeof(x))
#define sortall(x) sort(all(x))
#define PI 3.1415926535897932384626
#define MOD 1000000007

typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef vector<vi> vvi;
typedef vector<vl> vvl;

const ll mod = 1000000007;
const ll N = 3e5, M = N, ninf = -2e5;
vl g[N];
ll a[N], dp[N], in[N], out[N];
ll n;


bool ok;
ll curr_color;

bool dfs(ll u, ll par){
    ok = ok && (a[u] == curr_color);
    for(ll v: g[u]) {
        if (v == par) continue;
        dfs(v, u);
    }
}

bool solve(ll u){
    ll ans=true;
    for(ll v: g[u]){
        curr_color=a[v];
        ok=true;
        dfs(v, u);
        ans=ans && ok;
    }
    return ans;
}

int32_t main()
{
    IOS
    ll t,m,k,x,y,z,p,q,u,v,ct=0,flag=0,d;
    cin>>n;
    f(i,n-1) cin>>u>>v, g[u].pb(v), g[v].pb(u);
    fa(i,1,n+1) cin>>a[i];
    ll root1=-1;
    ll root2=-1;
    fa(i,1,n+1){
        for(ll ele: g[i]){
            if(a[ele]!=a[i]){
                root1=ele;
                root2=i;
                break;
            }
        }
    }
    if(root1==-1){
        cout<<"YES\n1";
        return 0;
    }
    bool res1=solve(root1);
    bool res2=solve(root2);
    if(res1){
        cout<<"YES\n"<<root1;
    }else if(res2){
        cout<<"YES\n"<<root2;
    }else{
        cout<<"NO";
    }
}