#include<bits/stdc++.h>
#define N 100030
using namespace std;

int lvl[N], dp[N][20],n,m;
vector<int>V[N];

void DFS(int x, int h) {
    lvl[x]=h;
    for (auto it:V[x]) {
        DFS(it,h+1);
    }
}

int main() {
    ifstream cin("lca.in");
    ofstream cout("lca.out");
    cin>>n>>m;
    for (int i=2; i<=n; ++i) {
        int x; cin>>x;
        V[x].push_back(i);
        dp[i][0]=x;
    }
    DFS(1,0);
    for (int j=1; (1<<j)<=n; ++j) {
        for (int i=1; i<=n; ++i) dp[i][j]=dp[dp[i][j-1]][j-1];
    }

    while (m--) {
        int x,y; cin>>x>>y;
        while (lvl[x]!=lvl[y]) {
            if (lvl[x]<lvl[y]) swap(x,y);
            int p=0;
            while (dp[x][p+1] &&  lvl[dp[x][p+1]]>lvl[y]) ++p;
            x=dp[x][p];
        }
        while (x!=y) {
            int p=0;
            while (dp[x][p+1]!=dp[y][p+1]) ++p;
            x=dp[x][p]; y=dp[y][p];
        }
        cout<<x<<'\n';
    }



    return 0;
}