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#include <iostream>
#include <bits/stdc++.h>
#include <fstream>
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
vector<int> G, L;
int n, m;
inline void rd()
{
int x=1;
f>>n>>m;
G.resize(n+1);
L.resize(n+1);
G[x]=-1;
L[x]=0;
while(x<n&&f>>G[++x])
L[x]=L[G[x]]+1;
}
inline int LCA(int x, int y)
{
if(L[x]<=L[y])
swap(x, y);
while(L[x]>L[y])
x=G[x];
while(x!=y)
{
x=G[x];
y=G[y];
}
return x;
}
int main()
{
int x, y;
rd();
while(f>>x>>y)
g<<LCA(x, y)<<'\n';
f.close();
g.close();
return 0;
}