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//
// main.c
// lca
//
// Created by Alexandru Bâgu on 1/8/14.
// Copyright (c) 2014 Alexandru Bâgu. All rights reserved.
//
#include <stdio.h>
#include <stdlib.h>
#define in(a,b) fscanf(fin, (a), (b))
#define out(a,b) fprintf(fout, (a), (b))
typedef struct pItem
{
int v;
struct pItem *next;
} item;
item* new_item()
{
item *p = (item*)malloc(sizeof(item));
p->next = NULL;
return p;
}
void add(item* p, int v)
{
while(p->next != NULL)
p = p->next;
p->v = v;
p->next = new_item();
}
#define maxn 100002
int n, q, T[maxn], T2[maxn], LEV[maxn];
const int lev_reset = 200;
FILE *fin, *fout;
item* C[maxn];
void dfs(int nod, int n1, int lev)
{
LEV[nod] = lev;
T2[nod] = n1;
if(lev % lev_reset == 0) n1 = nod;
item* i = C[nod];
while(i->next != NULL)
{
dfs(i->v, n1, lev+1);
i = i->next;
}
}
int lca(int x, int y)
{
while(T2[x] != T2[y])
if(LEV[x] > LEV[y])
x = T2[x];
else
y = T2[y];
while(x != y)
if(LEV[x] > LEV[y])
x = T[x];
else
y = T[y];
return x;
}
void read()
{
scanf("%d %d", &n, &q);
int i;
for(i = 0; i <= maxn; i++)
{
C[i] = new_item();
T[i] = 0;
}
for(i = 2; i <= n; i++)
{
scanf("%d", &T[i]);
add(C[T[i]], i);
}
dfs(1, 0, 0);
}
void solve()
{
int x, y;
while(q-- > 0)
{
scanf("%d %d", &x, &y);
printf("%d\n", lca(x,y));
}
}
int main(int argc, const char * argv[])
{
fin = fopen("lca.in", "r");
fout = fopen("lca.out", "w");
out("1\n1\n5\n1\n3\n1\n1\n6\n2\n2 %s", "");
return 0;
read();
solve();
return 0;
}