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#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define ld long double
#define chad char
#define mod 666013
#define dim 100005
#define lim 1000000
#define INF 1000000000
#define FOR(i,a,b) for(int i=(a); i<=(b); i++)
#define piii pair<int,pair<int,int> >
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pb push_back
#define mp make_pair
#define nr_biti __builtin_popcount
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int st[30][dim];
int n,m;
vector<int> g[dim];
int h[dim];
void dfs(int nod,int daddy=0)
{
h[nod]=1+h[daddy];
for(auto it:g[nod])
{
if(it==daddy)
continue;
dfs(it,nod);
}
}
void pre()
{
for(int i=1; (1<<i)<=n; i++)
for(int j=1; j<=n; j++)
st[i][j]=st[i-1][st[i-1][j]];
}
int bl(int nod,int niv)
{
int z=0;
while(niv)
{
if(niv&1)
nod=st[z][nod];
z++;
niv/=2;
}
return nod;
}
int lca(int x,int y)
{
if(h[x]>h[y])
swap(x,y);
int dif=h[y]-h[x];
y=bl(y,dif);
if(x==y)
return x;
for(int i=20; i>=0; i--)
{
if(st[i][x]!=st[i][y])
{
x=st[i][x];
y=st[i][y];
}
}
return st[0][x];
}
int main()
{
ios_base::sync_with_stdio(false);
fin.tie(nullptr);
fout.tie(nullptr);
fin >> n >> m;
for(int i=2; i<=n; i++)
{
fin >> st[0][i];
g[i].pb(st[0][i]);
g[st[0][i]].pb(i);
}
dfs(1);
pre();
while(m--)
{
int x,y;
fin >> x >> y;
fout << lca(x,y) << "\n";
}
return 0;
}