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#include <cstdio>
#include <vector>
#include <algorithm>
#define max(a, b) (a > b ? a : b)
#define NMAX 100005
using namespace std;
int n, m, k;
vector<int>v[NMAX];
int H[NMAX << 1], Lv[NMAX << 1], first[NMAX], lg[NMAX<<1];
int R[25][NMAX << 2];
void dfs(int nod,int niv)
{
H[++k]=nod;
Lv[k]=niv;
first[nod]=k;
for(int it = 0; it < v[nod].size(); ++it)
{
dfs(v[nod][it],niv+1);
H[++k]=nod;
Lv[k]=niv;
}
}
void citire()
{
int x;
freopen("lca.in", "r", stdin);
scanf("%d%d",&n,&m);
for(int i = 2; i <= n; ++i)
{
scanf("%d",&x);
v[x].push_back(i);
}
dfs(1,0);
}
void rmq()
{
for(int i = 2; i <= k; ++i)
lg[i] = lg[i/2] + 1;
for(int i = 1; i <= k; ++i)
R[0][i]=i;
for(int i = 1; (1 << i) < k; ++i)
for(int j = 1; j <= k - (1 << i); ++j)
{
int l = 1 << (i - 1);
R[i][j] = R[i-1][j];
if(Lv[R[i-1][j + l]] < Lv[R[i][j]])
R[i][j] = R[i-1][j + l];
}
}
int lca(int x, int y)
{
int dif, l, sol, sh;
int a = first[x], b = first[y];
if(a > b) swap(a, b);
dif = b - a + 1;
l = lg[dif];
sol = R[l][a];
sh = dif - (1 << l);
if(Lv[sol] > Lv[R[l][a + sh]])
sol = R[l][a + sh];
return H[sol];
}
void query()
{
int x,y;
freopen("lca.out", "w",stdout);
for(int i = 1; i <= m; ++i)
{
scanf("%d%d",&x,&y);
printf("%d\n",lca(x,y));
}
}
int main()
{
citire();
rmq();
query();
return 0;
}