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#include <cstdio>
#include <vector>
using namespace std;
vector <int> g[100001];
int euler[200001], nivel[200001], poz[200001], rmq[22][200001], lg[200001], n, m=1;
void RMQ (void)
{
int i, j, x;
for (i=2; i<=m; i++) lg[i]=lg[i/2]+1;
for (i=1; i<=m; i++) rmq[0][i]=i;
for (i=1; (1<<i)<=m; i++)
{
x=1<<(i-1);
for (j=1; j<=m-(1<<i)+1; j++)
{
if (nivel[rmq[i][j]]<nivel[rmq[i-1][j+x]]) rmq[i][j]=rmq[i-1][j];
if (nivel[rmq[i][j]]>=nivel[rmq[i-1][j+x]]) rmq[i][j]=rmq[i-1][j+x];
}
}
}
void dfs (int x, int p)
{
int i;
for (i=0; i<g[x].size(); i++)
{
euler[++m]=g[x][i];
nivel[m]=p+1;
poz[g[x][i]]=m;
dfs(g[x][i],p+1);
euler[++m]=x;
nivel[m]=p;
}
}
int lca (int p, int r)
{
int x, y, k, dif, q, sol;
x=poz[p]; y=poz[r];
if (x>y)
{
int aux=x;
x=y; y=aux;
}
dif=y-x+1;
k=lg[dif];
q=dif-(1<<k);
if (nivel[rmq[k][x]]<nivel[rmq[k][x+q]]) sol=rmq[k][x];
else sol=rmq[k][x+q];
if (euler[sol]!=0) return euler[sol];
else return 1;
}
int main()
{
int n, t, i, x, p, r;
freopen("lca.in","r",stdin);
freopen("lca.out","w",stdout);
scanf("%d%d",&n,&t); euler[1]=1;
for (i=2; i<=n; i++)
{
scanf("%d",&x);
g[x].push_back(i);
}
dfs(1,0);
RMQ();
for (i=1; i<=t; i++)
{
scanf("%d%d",&p,&r);
printf("%d\n",lca(p,r));
}
fclose(stdin);
fclose(stdout);
return 0;
}