#include <bits/stdc++.h>

using namespace std;

const int NMAX = 100003;
const int LOG = 16;
int n,m;
int depth[NMAX];
int up[NMAX][LOG+1];
vector<int>v[NMAX];

void dfs(int nod){
    for(int child:v[nod]){
        depth[child]=depth[nod]+1;
        up[child][0]=nod;
        for(int i=1;i<=LOG;i++)
            up[child][i]=up[up[child][i-1]][i-1];
        dfs(child);
    }
}
int get_lca(int x,int y){// O(N) solution
    if(depth[x] < depth[y])swap(x,y);
    while(depth[x] > depth[y])
        x = up[x][0];
    if(x==y)return x;
    while(x!=y){
        x=up[x][0];
        y=up[y][0];
    }
    return x;
}

int main(){
    freopen("lca.in","r",stdin);
    freopen("lca.out","w", stdout);
    scanf("%d %d",&n,&m);
    for(int i=1;i<n;i++){
        int x;
        scanf("%d",&x);
        v[x].push_back(i+1);
    }
    dfs(1);
    while(m--){
        int x,y;
        scanf("%d %d",&x,&y);
        printf("%d\n",get_lca(x,y) );
    }


    return 0;
}