#include <bits/stdc++.h>
// #include <windows.h>
// #include <bits/extc++.h>
// using namespace __gnu_pbds;
using namespace std;
//#pragma GCC optimize(3)
#define DB double
#define LL long long
#define ULL unsigned long long
#define in128 __int128
#define cint const int
#define cLL const LL
#define For(z,e1,e2) for(int z=(e1);z<=(e2);z++)
#define Rof(z,e1,e2) for(int z=(e2);z>=(e1);z--)
#define For_(z,e1,e2) for(int z=(e1);z<(e2);z++)
#define Rof_(z,e1,e2) for(int z=(e2);z>(e1);z--)
#define inint(e) scanf("%d",&e)
#define inll(e) scanf("%lld",&e)
#define inpr(e1,e2) scanf("%d%d",&e1,&e2)
#define in3(e1,e2,e3) scanf("%d%d%d",&e1,&e2,&e3)
#define outint(e) printf("%d\n",e)
#define outint_(e) printf("%d%c",e," \n"[i==n])
#define outint2_(e,e1,e2) printf("%d%c",e," \n"[(e1)==(e2)])
#define outll(e) printf("%lld\n",e)
#define outll_(e) printf("%lld%c",e," \n"[i==n])
#define outll2_(e,e1,e2) printf("%lld%c",e," \n"[(e1)==(e2)])
#define exc(e) if(e) continue
#define stop(e) if(e) break
#define ret(e) if(e) return
#define ll(e) (1ll*(e))
#define pb push_back
#define ft first
#define sc second
#define pii pair<int,int> 
#define pli pair<long long,int> 
#define vct vector 
#define clean(e) while(!e.empty()) e.pop()
#define all(ev) ev.begin(),ev.end()
#define sz(ev) ((int)ev.size())
#define debug(x) printf("%s=%d\n",#x,x)
#define x0 __xx00__
#define y1 __yy11__
#define ffo fflush(stdout)
cLL mod=998244353,G=404;
// cLL mod[2]={1686688681ll,1666888681ll},base[2]={166686661ll,188868881ll};
template <typename Type> void get_min(Type &w1,const Type w2) { if(w2<w1) w1=w2; } template <typename Type> void get_max(Type &w1,const Type w2) { if(w2>w1) w1=w2; }
template <typename Type> Type up_div(Type w1,Type w2) { return (w1/w2+(w1%w2?1:0)); }
template <typename Type> Type gcd(Type X_,Type Y_) { Type R_=X_%Y_; while(R_) { X_=Y_; Y_=R_; R_=X_%Y_; } return Y_; } template <typename Type> Type lcm(Type X_,Type Y_) { return (X_/gcd(X_,Y_)*Y_); }
template <typename Type> Type md(Type w1,const Type w2=mod) { w1%=w2; if(w1<0) w1+=w2; return w1; } template <typename Type> Type md_(Type w1,const Type w2=mod) { w1%=w2; if(w1<=0) w1+=w2; return w1; }
void ex_gcd(LL &X_,LL &Y_,LL A_,LL B_) { if(!B_) { X_=1ll; Y_=0ll; return ; } ex_gcd(Y_,X_,B_,A_%B_); X_=md(X_,B_); Y_=(1ll-X_*A_)/B_; } LL inv(LL A_,LL B_=mod) { LL X_=0ll,Y_=0ll; ex_gcd(X_,Y_,A_,B_); return X_; }
template <typename Type> void add(Type &w1,const Type w2,const Type M_=mod) { w1=md(w1+w2,M_); } void mul(LL &w1,cLL w2,cLL M_=mod) { w1=md(w1*md(w2,M_),M_); } template <typename Type> Type pw(Type X_,Type Y_,Type M_=mod) { Type S_=1; while(Y_) { if(Y_&1) mul(S_,X_,M_); Y_>>=1; mul(X_,X_,M_); } return S_; }
template <typename Type> Type bk(vector <Type> &V_) { auto T_=V_.back(); V_.pop_back(); return T_; } template <typename Type> Type tp(stack <Type> &V_) { auto T_=V_.top(); V_.pop(); return T_; } template <typename Type> Type frt(queue <Type> &V_) { auto T_=V_.front(); V_.pop(); return T_; }
template <typename Type> Type bg(set <Type> &V_) { auto T_=*V_.begin(); V_.erase(V_.begin()); return T_; } template <typename Type> Type bk(set <Type> &V_) { auto T_=*prev(V_.end()); V_.erase(*prev(V_.end())); return T_; }
mt19937 gen(time(NULL)); int rd() { return abs((int)gen()); }
int rnd(int l,int r) { return rd()%(r-l+1)+l; }

void main_init()
{

}
cint N=1.02e5,N2=N<<1;
cLL inf=1e18;
int n,n2,Q;
array <int,2> son[N2];
int rt,up[N2]; // bool gt[N2];
LL val[N2];
array <LL,2> h[N2];
int dfs(int p)
{
    if(p<=n) return 0;
    int re=max(dfs(son[p][0]),dfs(son[p][1]))+1;
    h[p]={val[son[p][0]],val[son[p][1]]};
    val[p]=h[p][0]+h[p][1];
    // printf("%d:%lld\n",p,val[p]);
    return re;
}
multiset <array<LL,2> > st;
int cnt;
void Ins(array <LL,2> &w)
{
    st.insert(w);
    auto iter=st.find(w),iter2=iter; iter2++;
    array <LL,2> pre=(iter==st.begin()?(array<LL,2>){-inf,-inf}:*prev(iter));
    array <LL,2> suf=(iter2==st.end()?(array<LL,2>){inf,inf}:*iter2);
    cnt+=((pre[1]>w[0])+(w[1]>suf[0])-(pre[1]>suf[0]));
}
void Ers(array <LL,2> &w)
{
    auto iter=st.find(w),iter2=iter; iter2++;
    array <LL,2> pre=(iter==st.begin()?(array<LL,2>){-inf,-inf}:*prev(iter));
    array <LL,2> suf=(iter2==st.end()?(array<LL,2>){inf,inf}:*iter2);
    cnt-=((pre[1]>w[0])+(w[1]>suf[0])-(pre[1]>suf[0]));
    st.erase(iter);
}
void init()
{
    if(dfs(rt)>=80)
    {
        while(Q--) printf("NO\n");
        exit(0);
    }
    For(i,n+1,n2)
    {
        if(h[i][0]>h[i][1]) swap(h[i][0],h[i][1]);
        Ins(h[i]);
    }
}
void change(int k,LL w)
{
    val[k]=w;
    for(int i=up[k];i;i=up[i])
    {
        Ers(h[i]);
        h[i]={val[son[i][0]],val[son[i][1]]};
        if(h[i][0]>h[i][1]) swap(h[i][0],h[i][1]);
        val[i]=h[i][0]+h[i][1];
        Ins(h[i]);
    }
}
void main_solve()
{
    inpr(n,Q); n2=(n<<1)-1;
    For(i,1,n) inll(val[i]);
    For(i,n+1,n2)
    {
        inpr(son[i][0],son[i][1]);
        up[son[i][0]]=up[son[i][1]]=i;
        // gt[son[i][0]]=false,gt[son[i][1]]=true;
    }
    rt=1; For(i,1,n2) if(!up[i]) rt=i;
    // printf("rt=%d\n",rt);
    cnt=0;
    init();
    printf("%s\n",cnt?"NO":"YES");
    Q--; while(Q--)
    {
        int k; LL w; scanf("%d%lld",&k,&w);
        val[k]=w;
        change(k,w);
        printf("%s\n",cnt?"NO":"YES");
    }
}
int main()
{
    // ios::sync_with_stdio(0); cin.tie(0);
    // freopen("in.txt","r",stdin);
    // freopen("out.txt","w",stdout);
    // srand(time(NULL));
    main_init();
    // int _; inint(_); For(__,1,_) // T>1 ?
        // printf("\n------------\n\n"),
        main_solve();
    return 0;
}
/*

*/