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#include <iostream>
#include <fstream>
#include <vector>
#define NMAX 105
#define LOGMAX 18
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int n,m,depth[2*NMAX],euler[2*NMAX],top=0,lvl=1,index[NMAX],M[LOGMAX][NMAX],log[2*NMAX];
bool viz[NMAX];
vector <int> g[NMAX];
void dfs(int nod) {
viz[nod]=1;
euler[++top]=nod;
depth[top]=lvl;
if(!index[nod])
index[nod]=top;
for(int i=0; i<g[nod].size(); i++) {
int aux=g[nod][i];
if(!viz[aux]) {
lvl++;
dfs(aux);
lvl--;
euler[++top]=nod;
depth[top]=lvl;
if(!index[nod])
index[nod]=top;
}
}
}
void logarithm() {
log[1]=0;
for(int i=2;i<=top;i++)
log[i]=log[i/2]+1;
}
void rmq() {
for(int i=1;i<=top;i++)
M[0][i]=i;
for(int i=1;(1<<i)<=top;i++)
for(int j=1;j+(1<<i)-1<=top;j++) {
int k=1<<(i-1);
if(depth[M[i-1][j]]<depth[M[i-1][j+k]])
M[i][j]=M[i-1][j];
else
M[i][j]=M[i-1][j+k];
}
}
int main() {
fin>>n>>m;
for(int i=2; i<=n; i++) {
int x;
fin>>x;
g[i].push_back(x);
g[x].push_back(i);
}
dfs(1);
logarithm();
rmq();
for(int i=1;i<=m;i++) {
int x,y;
fin>>x>>y;
int k=log[index[y]-index[x]+1];
fout<<euler[min(M[k][index[x]],M[k][index[y]-(1<<k)+1])]<<"\n";
}
return 0;
}