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#include <bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int par[100005][19];
int tin[100005],tout[100005],timp,viz[100005];
vector <int> v[100005];
int n,m,x,y;
void dfs(int nod)
{
tin[nod]=++timp;
viz[nod]=1;
for(int i=0;i<v[nod].size();i++)
if(!viz[v[nod][i]])
dfs(v[nod][i]);
tout[nod]=++timp;
}
bool is_ancestor(int x,int y)
{
if(x==0||x==y)
return 1;
if((tin[x]<tin[y]&&tout[x]>tout[y]))
return 1;
return 0;
}
int lca(int x,int y)
{
if(is_ancestor(x,y))
return x;
if(is_ancestor(y,x))
return y;
for(int i=18;i>=0;i--)
{
if(!is_ancestor(par[x][i],y))
x=par[x][i];
}
return par[x][0];
}
int main()
{
fin>>n>>m;
for(int i=2;i<=n;i++)
{
fin>>par[i][0];
v[par[i][0]].push_back(i);
}
for(int j=1;j<=18;j++)
for(int i=1;i<=n;i++)
{
par[i][j]=par[par[i][j-1]][j-1];
}
dfs(1);
for(int i=1;i<=m;i++)
{
fin>>x>>y;
fout<<lca(x,y)<<'\n';
}
return 0;
}