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#include <cstdio>
#include <vector>
using namespace std;
vector<int> v[100010];
int niv[100010],tata[20][100010],logn;
void dfs(int nod,int dad,int lev)
{
tata[0][nod]=dad;
niv[nod]=lev;
for(int i=1;i<=logn;i++) tata[i][nod]=tata[i-1][tata[i-1][nod]];
for(vector<int>::iterator it=v[nod].begin();it!=v[nod].end();it++)
dfs(*it,nod,lev+1);
}
int lca(int x,int y)
{
if(niv[x]<niv[y]) swap(x,y);
for(int i=logn;i>=0;i--)
if(niv[tata[i][x]]>=niv[y]) x=tata[i][x];
for(int i=logn;i>=0;i--)
if(tata[i][x]!=tata[i][y]) {x=tata[i][x];y=tata[i][y];}
if(x==y) return x;
else return tata[0][x];
}
int main()
{
freopen("lca.in", "r", stdin);
freopen("lca.out", "w", stdout);
int n,m,x,y;
scanf("%d%d",&n,&m);
for(int i=2;i<=n;i++)
{
scanf("%d",&x);
v[x].push_back(i);
}
for(logn=1;1<<logn<=n;logn++);logn--;
dfs(1,0,1);
for(int i=1;i<=m;i++)
{
scanf("%d%d",&x,&y);
printf("%d\n",lca(x,y));
}
return 0;
}