#include<cstdio>
#include<vector>
using namespace std;
int n,m,x,y,i,nivel[100007],tata[100007];
vector<int>v[100007];

void dfs(int x,int l,int t)
{
    int j;
    tata[x]=t;
    nivel[x]=l;
    t=x;
    for(j=0;j<v[x].size();j++)dfs(v[x][j],l+1,t);
}

void citire()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    scanf("%d %d",&n,&m);
    for(i=1;i<n;i++)scanf("%d",&x),v[x].push_back(i+1);
}

void lca(int x,int y)
{
    while(x!=y)
    if(nivel[x]>nivel[y])x=tata[x];
                    else y=tata[y];
    printf("%d\n",x);
}

int main()
{
    citire();
    dfs(1,0,0);
    for(i=1;i<=m;i++)scanf("%d %d",&x,&y),lca(x,y);
    return 0;
}