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//Lowest Common Ancestor
//Complexitate : Memorie O(n) , Timp O(n*m);
#include <cstdio>
#include <vector>
#define nmax 100005
using namespace std;
int n,m,t[nmax],g[nmax];
vector <int> v[nmax];
void dfs(int x)
{
int i;
for (i=0;i<v[x].size();i++) {
g[v[x][i]]=g[x]+1;
dfs(v[x][i]);
}
}
int main()
{
freopen("lca.in","r",stdin);
freopen("lca.out","w",stdout);
int i,j,a,b;
scanf("%d %d",&n,&m);
for (i=2;i<=n;i++) {
scanf("%d",&t[i]);
v[t[i]].push_back(i);
}
dfs(1);
for (i=1;i<=m;i++) {
scanf("%d %d",&a,&b);
while (a!=b) {
if (g[a]>g[b])
a=t[a];
else
b=t[b];
}
printf("%d\n",a);
}
return 0;
}