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#include<cstdio>
#include<fstream>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<vector>
#include<bitset>
#include<deque>
#include<queue>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<unordered_map>
#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<ll,ll>
using namespace std;
const int nmax = 100005;
const int lmax = 18;
int n, q, x, y, i, j, dif, lim, logg, f[lmax][nmax], lev[nmax];
vector<int> v[nmax];
void dfs(int x)
{
for(auto it : v[x])
{
lev[it] = lev[x] + 1;
dfs(it);
}
}
int main()
{
freopen("lca.in", "r", stdin);
freopen("lca.out", "w", stdout);
scanf("%d%d", &n, &q);
for(i = 2; i <= n; i++)
{
scanf("%d", &f[0][i]);
v[f[0][i]].push_back(i);
}
for(i = 1; (1 << i) <= n; i++)
for(j = 1; j <= n; j++)
f[i][j] = f[i - 1][f[i - 1][j]];
lev[1] = 1;
dfs(1);
for(lim = 1, logg = 2; lim <= n; lim *= 2, logg++);
for(; q; q--)
{
scanf("%d%d", &x, &y);
if(lev[x] > lev[y])
swap(x, y);
dif = lev[y] - lev[x];
for(i = 0; i <= logg; i++)
if((1 << i) & dif)
y = f[i][y];
if(x == y)
{
printf("%d\n", x);
continue;
}
for(i = logg; i >= 0; i--)
if(f[i][x] != f[i][y])
{
x = f[i][x];
y = f[i][y];
}
printf("%d\n", f[0][x]);
}
return 0;
}