///////////////////////////////////////////////////////////////////////////////

#include <bits/stdc++.h>
#include <unistd.h>
#include <time.h>
#include <sys/time.h>

using namespace std;

///////////////////////////////////////////////////////////////////////////////

#define DEBUG 0

#define pb push_back
#define V vector
#define M unordered_map
#define S static
#define PI  (3.1415926535)

#define rep(i,n) for(ll i=0LL; i<n; ++i)
#define srep(i,s,n) for(ll i=s; i<n; ++i)
#define rrep(i,n) for(ll i=n-1LL; i>=0LL; --i)
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define CIN(x) do { \
        assert(!cin.eof()); \
        cin >> x; \
        assert(!cin.fail()); \
} while(0);
#if DEBUG
#define debug_print(...) _debug_print(__VA_ARGS__)
#define debug_printf(...) printf(__VA_ARGS__)
#define debug_print_time _debug_print_time
#else // DEBUG
#define debug_print(...)
#define debug_printf(...)
#define debug_print_time
#endif // DEBUG

typedef long long ll;
typedef unsigned long long ull;
typedef tuple<ll, ll> t2;
typedef tuple<ll, ll, ll> t3;
typedef tuple<ll, ll, ll, ll> t4;
typedef tuple<ll, ll, ll, ll, ll> t5;
template <typename T>
using priority_queue_incr = priority_queue<T, V<T>, greater<T> >;

///////////////////////////////////////////////////////////////////////////////

template <typename TT, typename T>
T get_m(M<TT, T> &m, TT k, T default_value)
{
    if (m.find(k) == m.end()) return m[k] = default_value;
    return m[k];
}

template <typename TT, typename T>
void incr_m(M<TT, T> &m, TT k)
{
    if (m.find(k) == m.end()) m[k] = 0;
    m[k]++;
}

void llin(ll &a)
{
    CIN(a);
}

void llinl1(auto &v, ll count)
{
    for (ll i = 0LL; i < count; ++i) {
        ll a;
        CIN(a);
        v.push_back(a);
    }
}

void llinl2(auto &v, ll count)
{
    for (ll i = 0LL; i < count; ++i) {
        ll a, b;
        CIN(a >> b);
        v.push_back(t2(a, b));
    }
}

void llinl3(auto &v, ll count)
{
    for (ll i = 0LL; i < count; ++i) {
        ll a, b, c;
        CIN(a >> b >> c);
        v.push_back(t3(a, b, c));
    }
}

void llinl4(auto &v, ll count)
{
    for (ll i = 0LL; i < count; ++i) {
        ll a, b, c, d;
        CIN(a >> b >> c >> d);
        v.push_back(t4(a, b, c, d));
    }
}

void llina(auto &v, ll count)
{
    llinl1(v, count);
}

template <typename T>
void sort(V<T> &v)
{
    sort(v.begin(), v.end());
}

template <typename T>
void sort_reverse(V<T> &v)
{
    sort(v.begin(), v.end(), greater<T>());
}

void _debug_print(auto x)
{
    cout << x << endl;
}

void _debug_print(const t2 &x)
{
    ll x1 = get<0>(x);
    ll x2 = get<1>(x);
    cout << "-- " << x1 << " -- " << x2 << endl;
}

void _debug_print(const t3 &x)
{
    ll x1 = get<0>(x);
    ll x2 = get<1>(x);
    ll x3 = get<2>(x);
    cout << "-- " << x1 << " -- " << x2 << " -- " << x3 << endl;
}

void _debug_print(const t4 &x)
{
    ll x1 = get<0>(x);
    ll x2 = get<1>(x);
    ll x3 = get<2>(x);
    ll x4 = get<3>(x);
    cout << "-- " << x1 << " -- " << x2
         << " -- " << x3 << " -- " << x4 << endl;
}

template <typename T>
void _debug_print(T xarray[], ll n)
{
    rep (i, n) _debug_print(xarray[i]);
}

template <typename T>
void _debug_print(const V<T> &xlist)
{
    for (auto x : xlist) {
        cout << "-- ";
        _debug_print(x);
    }
}

template <typename T>
void _debug_print(const set<T> &xset)
{
    for (auto x : xset) {
        cout << "-- ";
        _debug_print(x);
    }
}

template <typename TT, typename T>
void _debug_print(const M<TT, T> &xlist)
{
    for (auto x : xlist) {
        TT k = x.first;
        T v = x.second;
        cout << "====" << endl;
        cout << "K=";
        _debug_print(k);
        cout << "V=";
        _debug_print(v);
    }
}

void _debug_print_time(const char *prefix)
{
    struct timeval tv;
    gettimeofday(&tv, NULL);
    struct tm *tm = localtime(&tv.tv_sec);
    printf("-- %s %02d:%02d:%02d.%06ld\n",
           prefix, tm->tm_hour, tm->tm_min, tm->tm_sec, tv.tv_usec);
}



void make_edgelist(const V<t2> &srclist, V<ll> edgelist[])
{
    for (auto src : srclist) {
        ll a = get<0>(src);
        ll b = get<1>(src);
        edgelist[a].pb(b);
        edgelist[b].pb(a);
    }
}




void make_parental_relation(const V<ll> edgelist[], ll root, ll n,
                            ll parents[], V<ll> children[], ll levels[])
{
    queue<ll> q;
    bool checked[n+1];

    memset(checked, 0, sizeof(checked));

    q.push(root);
    checked[root] = true;
    parents[root] = root;
    levels[root] = 0LL;

    for ( ; !(q.empty()); ) {
        ll now = q.front(); q.pop();
        for (auto next : edgelist[now]) {
            if (checked[next]) continue;
            q.push(next);
            checked[next] = true;
            parents[next] = now;
            children[now].pb(next);
            levels[next] = levels[now] + 1LL;
        }
    }
}



///////////////////////////////////////////////////////////////////////////////

void _main();
int main()
{
    cout << setprecision(12);
#if !DEBUG
    ios::sync_with_stdio(false);
    cin.tie(0);
#endif

    _main();
    return 0;
}

void _main()
{
    ll n; llin(n);
    S V<ll> alist; alist.pb(-1e18); llina(alist, n);
    S V<t2> uvlist; llinl2(uvlist, n-1);

    S V<ll> edgelist[100005];
    make_edgelist(uvlist, edgelist);

    S ll parents[100005];
    S V<ll> children[100005];
    S ll levels[100005];
    make_parental_relation(edgelist, 1, n, parents, children, levels);

    S ll ccnt[100005];
    srep (v, 1, n+1) ccnt[v] = children[v].size();

    S queue<ll> q;
    srep (v, 2, n+1) if (ccnt[v] == 0) q.push(v);

    S V<ll> stonecnts[100005];

    while (q.size()) {
        ll v = q.front(); q.pop();
        ll pv = parents[v];

        if (stonecnts[v].empty()) {
            stonecnts[pv].pb(alist[v]);
            ccnt[pv]--; if (!ccnt[pv] && v != 1) q.push(pv);
            continue;
        }

        ll maxcnt = 0;
        for (auto scnt : stonecnts[v]) maxcnt = max(maxcnt, scnt);
        ll totalcnt = 0;
        for (auto scnt : stonecnts[v]) totalcnt += scnt;

        ll upcnt = max(0LL, maxcnt - (totalcnt - maxcnt));
        ll anycnt = totalcnt - upcnt;
        ll maxa = totalcnt;
        ll mina = upcnt + anycnt / 2LL + (anycnt & 1LL);
        ll a = alist[v];
        if (a < mina || maxa < a) {
            debug_printf("v=%lld a=%lld mina=%lld maxa=%lld\n", v, a, mina, maxa);
            debug_printf("---- no 1\n");
            cout << "NO" << endl;
            return;
        }

        ll realupcnt = a * 2LL - totalcnt;
        debug_printf("v=%lld realupcnt=%lld\n", v, realupcnt);

        if (v == 1) {
            bool ng = false;
            if (children[v].size() == 1) ng = (realupcnt != a);
            else ng = !!(realupcnt);

            if (ng) {
                debug_printf("---- no 2\n");
                cout << "NO" << endl;
                return;
            }

            continue;
        }

        stonecnts[pv].pb(realupcnt);
        ccnt[pv]--; if (!ccnt[pv] && v != 1) q.push(pv);
    }

    cout << "YES" << endl;
}

///////////////////////////////////////////////////////////////////////////////


Measured memory_bytes: 21488