#include<iostream>
#include<cstdio>
#include<set>
#define N 200000
using namespace std;
long long read()
{
	char c=0;
	long long sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
struct reads
{
	int num;
	long long l,r;
	bool operator < (const reads &t)const
	{
		if (l!=t.l) return l<t.l;
		else if (r!=t.r) return r<t.r;
		else return num<t.num;
	}
};
set<reads>s;
int n,q,cnt,fa[N+1],ls[N+1],rs[N+1],depth[N+1],maxn;
long long a[N+1],delta[N+1];
void adder(reads d,int op)
{
	if (op==1)
	{
		long long pv=-1,nt=-1;
		auto it=s.lower_bound(d);
		if (it!=s.end()) nt=(*it).l;
		if (it!=s.begin()) it--,pv=(*it).r;
		if (pv!=-1&&nt!=-1) cnt-=(pv>nt);
		if (pv!=-1) cnt+=(pv>d.l);
		if (nt!=-1) cnt+=(d.r>nt);
		s.insert(d);
	}
	else
	{
		long long pv=-1,nt=-1;
		s.erase(d);
		auto it=s.lower_bound(d);
		if (it!=s.end()) nt=(*it).l;
		if (it!=s.begin()) it--,pv=(*it).r;
		if (pv!=-1&&nt!=-1) cnt+=(pv>nt);
		if (pv!=-1) cnt-=(pv>d.l);
		if (nt!=-1) cnt-=(d.r>nt);
	}
	return;
}
void dfs(int x)
{
	maxn=max(maxn,depth[x]);
	if (ls[x]) depth[ls[x]]=depth[rs[x]]=depth[x]+1,dfs(ls[x]),dfs(rs[x]),delta[x]=delta[ls[x]]+delta[rs[x]],adder((reads){x,min(delta[ls[x]],delta[rs[x]]),max(delta[ls[x]],delta[rs[x]])},1);
	else delta[x]=a[x];
	return;
}
int main()
{
	int p,x;
	long long d;
	n=read(),q=read();
	for (int i=1;i<=n;++i) a[i]=read();
	for (int i=n+1;i<=(n<<1)-1;++i) ls[i]=read(),rs[i]=read(),fa[ls[i]]=fa[rs[i]]=i;
	dfs((n<<1)-1);
	if (maxn>=60)
	{
		for (int i=1;i<=q;++i) puts("NO");
		return 0;
	}
	puts(!cnt?"YES":"NO");
	for (int qt=1;qt<=q-1;++qt)
	{
		p=read(),x=read(),d=x-a[p],a[p]=x;
		while (p!=(n<<1)-1)
		{
			adder((reads){fa[p],min(delta[ls[fa[p]]],delta[rs[fa[p]]]),max(delta[ls[fa[p]]],delta[rs[fa[p]]])},-1);
			delta[p]+=d;
			adder((reads){fa[p],min(delta[ls[fa[p]]],delta[rs[fa[p]]]),max(delta[ls[fa[p]]],delta[rs[fa[p]]])},1);
			p=fa[p];
		}
		puts(!cnt?"YES":"NO");
	}
	return 0;
}