#include <fstream>
#include <list>

using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

const int H = 400;

int n,i,x,y,m;
int nv[100005];
int tt[100005];
int ttm[100005];
list<int>ls[100005];

void df(int x, int tm, int niv) {
    ttm[x] = tm;
    if (niv%H == 0)
        tm = x;
    nv[x] = niv;
    int i, l = ls[x].size(), y;
    list<int>::iterator w;
    for (w = ls[x].begin(); w!=ls[x].end(); w++) {
        y = *w;
        if (nv[y] == 0)
            df(y,x,niv+1);
    }
}

int query(int x, int y) {
    while (ttm[x]!=ttm[y]) {
        if (nv[x]>nv[y])
            x = ttm[x];
        else if (nv[x]<nv[y])
            y = ttm[y];
        else x=ttm[x],y=ttm[y];

    }
    while (x != y) {
        if (nv[x]>nv[y])
            x = tt[x];
        else if (nv[x]<nv[y])
            y = tt[y];
        else x=tt[x],y=tt[y];
    }
    return x;
}

int main() {
    f >> n >> m;
    for (i = 2; i <= n; i++) {
        f >> tt[i];
        ls[tt[i]].push_back(i);
    }
    df(1,0,0);
    while (m--) {
        f >> x >> y;
        g << query(x,y) << '\n';
    }
    return 0;
}