#include <bits/stdc++.h>
using namespace std ;
const int MAX = 2e5 + 10 ;
int P[MAX][20] , Max[MAX][20] , Min[MAX][20] ;
int dep[MAX] ;
vector< vector<int> >adj(MAX) ;
int n , q ;
void dfs(int node)
{
Max[node][0] = -1 , Min[node][0] = 1e9 ;
if(adj[node].size() > 1)
Max[node][0] = dep[node] , Min[node][0] = dep[node] ;
for(int j = 1 ; j < 18 ; ++j)
{
P[node][j] = P[P[node][j-1]][j-1] ;
Max[node][j] = max(Max[node][j-1] , Max[P[node][j-1]][j-1]) ;
Min[node][j] = min(Min[node][j-1] , Min[P[node][j-1]][j-1]) ;
}
for(auto &child : adj[node])
{
dep[child] = dep[node] + 1 ;
dfs(child) ;
}
}
int LCA(int x , int y)
{
if(dep[x] < dep[y])
swap(x , y) ;
for(int j = 17 ; j >= 0 ; --j)
{
if(dep[x] - (1 << j) >= dep[y])
x = P[x][j] ;
}
if(x == y)
return x ;
for(int j = 17 ; j >= 0 ; --j)
{
if(P[x][j] != P[y][j])
x = P[x][j] , y = P[y][j] ;
}
return P[x][0] ;
}
int FindMax(int x , int y)
{
int a = -1 ;
for(int j = 17 ; j >= 0 ; --j)
{
if(dep[x] - (1 << j) >= dep[y])
a = max(a , Max[x][j]) , x = P[x][j] ;
}
return a ;
}
int FindMin(int x , int y)
{
int a = 1e9 ;
for(int j = 17 ; j >= 0 ; --j)
{
if(dep[x] - (1 << j) >= dep[y])
a = min(a , Min[x][j]) , x = P[x][j] ;
}
if(a == 1e9)
a = -1 ;
return a ;
}
int main()
{
ios_base::sync_with_stdio(0) ;
cin.tie(0) ;
cin>>n>>q ;
for(int i = 2 ; i <= n ; ++i)
{
cin>>P[i][0] ;
adj[P[i][0]].push_back(i) ;
}
dfs(1) ;
while(q--)
{
int a , b ;
cin>>a>>b ;
if(adj[b].size() > 0)
{
cout<<"yes\n" ;
continue ;
}
int lca = LCA(a , b) ;
int x = FindMax(b , lca) , dist1 = 0 , dist2 = 0 ;
if(x != -1)
dist1 = dep[a] + x - 2 * dep[lca] , dist2 = dep[b] - x ;
else if(adj[lca].size() > 2 || lca != 1 || (adj[lca].size() > 1 && (lca == a || lca == b)))
dist1 = dep[a] - dep[lca] , dist2 = dep[b] - dep[lca] ;
else if(FindMin(a , lca))
dist1 = dep[a] - FindMin(a , lca) , dist2 = dep[b] + FindMin(a , lca) - 2 * dep[lca] ;
if(dist1 > dist2)
cout<<"yes\n" ;
else
cout<<"no\n" ;
}
return 0 ;
}
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