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#include <fstream>
#include <vector>
#define NMax 100005
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
vector <int> G[NMax];
int N,M;
int TT[20][NMax],Level[NMax],Log[NMax];
void ReadTree()
{
fin>>N>>M;
for(int i=2;i<=N;i++)
{
fin>>TT[0][i];
G[TT[0][i]].push_back(i);
}
}
void Build()
{
for(int i=2;i<=N;i++)
Log[i] = Log[i/2] + 1;
for(int i = 1; (1<<i)<=N; i++)
for(int j = 1; j<=N; j++)
TT[i][j] = TT[i-1][TT[i-1][j]];
}
void DFS(int Node)
{
for(int i=0;i<(int)G[Node].size();i++)
{
int Vecin = G[Node][i];
Level[Vecin] = Level[Node] + 1;
DFS(Vecin);
}
}
int LCA(int x, int y)
{
if(Level[x]<Level[y])
swap(x,y);
while(Level[x]!=Level[y])
{
int K = Log[Level[x]-Level[y]];
x = TT[K][x];
}
if(x == y)
return x;
for(int K = Log[Level[x]]; K >=0 ;K--)
{
if(TT[K][x]!=TT[K][y])
{
x = TT[K][x];
y = TT[K][y];
}
}
return TT[0][x];
}
void SolveandPrint()
{
while(M--)
{
int x,y;
fin>>x>>y;
fout<<LCA(x,y)<<"\n";
}
}
int main()
{
ReadTree();
DFS(1);
Build();
SolveandPrint();
return 0;
}