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#include <fstream>
#include <vector>
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
#define min(a,b) (a<b?a:b)
int n,m,k,b[100005<<1],lev[100005<<1],prim[100005],rmq[20][100005<<2],lg[100005<<1];
vector <int> G[100005];
#define foreach(V) for(typeof (V).begin() it = (V).begin(); it != (V).end(); ++it)
void citire(){
f>>n>>m;
int x,i;
for(i=2;i<=n;i++)
{
f>>x;
G[x].push_back(i);
}
}
void rec(int nod, int lv){
b[++k]=nod;
lev[k]=lv;
prim[nod]=k;
foreach(G[nod])
{
rec(*it,lv+1);
b[++k]=nod;
lev[k]=lv;
}
}
void calcrmq()
{
int i,j;
for(i=2;i<=k;i++)
lg[i]=lg[i/2]+1;
for(i=1;i<=k;i++)
rmq[0][i]=b[i];
for(i=1;(1<<i)<=k;i++)
for(j=1;j<=k-(1<<i)+1;j++)
rmq[i][j]= min( rmq[i-1][j] , rmq[i-1][j+(1<<(i-1))] );
}
int lca(int x, int y){
int dif1,l,sol,dif2 ;
int a1 = prim[x], b1 = prim[y];
if(a1 > b1) swap(a1, b1);
dif1 = b1 - a1 + 1;
l = lg[dif1];
sol = rmq[l][a1];
dif2 = dif1 - (1 << l);
if(lev[sol] > lev[rmq[l][a1 + dif2]])
sol = rmq[l][a1 + dif2];
return sol;
}
int main()
{
int x,y,i;
citire();
rec(1,1);
calcrmq();
/* for(i=0;(1<<i)<=k;i++)
{
for(j=1;j<=k-(1<<i)+1;j++)
g<<rmq[i][j]<<" ";
g<<"\n";
}*/
for(i=1;i<=m;i++)
{
f>>x>>y;
g<<lca(x,y)<<"\n";
}
return 0;
}