#include <iostream>
#include <fstream>
using namespace std;

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

int arbt[100001], niv[100001], n;

int lca(int a, int b)   {
int c, nivc;
while (niv[a] != niv[b])   {
    if (niv[a]>niv[b])
        a = arbt[a];
    else
        b = arbt[b];
}
while (arbt[a] != arbt[b])  {
    a = arbt[a];
    b = arbt[b];
}
c = arbt[a];
return c;
}

int main()
{
    int i, x, y, m, j, rad;
    f>>n>>m;
    for (i=1;i<=n;i++)  {
        f>>arbt[i];
        if (arbt[i]==0)
            rad = i;
    }
    niv[rad]=1;

    int dist;
    for (i=1;i<=m;i++)  {
        f>>x>>y;
        g<<lca(x,y)<<"\n";

    }



    return 0;
}