#include <bits/stdc++.h>
using namespace std;
#define ll long long int
#define ld long double
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define PI 3.1415926535
#define fast ios::sync_with_stdio(false),cin.tie(NULL),cout.tie(NULL)
typedef pair<ll,ll> pli;
typedef pair<int,int> pii;
typedef pair<ld,ld> pld;
ll MOD=1000000007 ;
ll MX=1000000000000000;
const int N=200200;
ll n,q;
vector<ll>adj[N];
ll p[N];
ll tin[N];
ll lev[N];
ll tout[N];
ll up[30][N];
ll sons[30][N];
ll logn=19;
ll timer=0;
void dfs(int x,int p,int l)
{
tin[x]=++timer;
lev[x]=l;
up[0][x]=p;
if(adj[x].size()>1)
{
sons[0][x]=lev[x];
}
else
{
sons[0][x]=0;
}
for(int i=1;i<=logn;i++)
{
up[i][x]=up[i-1][up[i-1][x]];
sons[i][x]=max(sons[i-1][x],sons[i-1][up[i-1][x]]);
}
for(int i=0;i<adj[x].size();i++)
{
int nod=adj[x][i];
if(nod!=p)
dfs(nod,x,l+1);
}
tout[x]=++timer;
}
bool is_parent(int x,int y)
{
return (tin[x]<=tin[y]&&tout[x]>=tout[y]);
}
int lca(int a,int b)
{
if(is_parent(a,b))
return a;
if(is_parent(b,a))
return b;
for(int i=logn;i>=0;i--)
{
if(!is_parent(up[i][a],b))
{
a=up[i][a];
}
}
return up[0][a];
}
ll nearest_sol(ll a,ll b)
{
ll res=0;
for(int i=logn;i>=0;i--)
{
if(!is_parent(up[i][a],b))
{
res=max(res,sons[i][a]);
a=up[i][a];
}
}
return res;
}
ll dis(ll x,ll y)
{
return lev[x]+lev[y]-2*lev[lca(x,y)];
}
int main()
{
fast;
//freopen("input.txt","r",stdin);
cin>>n>>q;
ll is_linear=1;
for(int i=2;i<=n;i++)
{
cin>>p[i];
adj[p[i]].pb(i);
}
for(int i=1;i<=n;i++)
{
if(adj[i].size()>1)
is_linear=0;
}
ll a,b;
dfs(1,1,1);
while(q--)
{
cin>>a>>b;
ll lc=lca(a,b);
if(a==b)
{
cout<<"yes\n";
}
else
{
if(is_parent(b,a))
{
if(b==1)
{
if(adj[a].size()>0)
{
cout<<"yes\n";
}
else
{
ll nod=nearest_sol(b,lc);
if(nod==0)
cout<<"no\n";
else if(lev[b]-nod<lev[a]-lev[lc]+nod-lev[lc])
cout<<"yes\n";
else
cout<<"no\n";
}
}
else
{
cout<<"yes\n";
}
}
else if(is_parent(a,b))
{
if(adj[b].size()>0)
{
cout<<"yes\n";
}
else
{
if(dis(b,lc)<dis(a,lc))
{
cout<<"yes\n";
}
else
{
ll nod=nearest_sol(b,lc);
if(nod==0)
cout<<"no\n";
else if(lev[b]-nod<lev[a]-lev[lc]+nod-lev[lc])
cout<<"yes\n";
else
cout<<"no\n";
}
}
}
else
{
ll lc=lca(a,b);
if(dis(b,lc)<dis(a,lc))
{
cout<<"yes\n";
}
else
{
ll nod=nearest_sol(b,lc);
if(nod==0)
cout<<"no\n";
else if(lev[b]-nod<lev[a]-lev[lc]+nod-lev[lc])
cout<<"yes\n";
else
cout<<"no\n";
}
}
}
}
return 0;
}
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