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#include <bits/stdc++.h>
#define NMAX 100005
#define LGMAX 18
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int n,m;
int lev[NMAX];
int dp[LGMAX][NMAX];
vector<int> g[NMAX];
void dfs(int n,int l) {
lev[n]=l;
for(auto& q:g[n])
dfs(q,l+1);
}
int lca(int x,int y) {
if(lev[x]<lev[y]) swap(x,y);
int log1,log2;
for(log1=0;(1<<log1)<lev[x];log1++);
for(log2=0;(1<<log2)<lev[y];log2++);
for(int k=log1;k>=0;k--) {
if(lev[x]-(1<<k)>=lev[y]) {
x=dp[k][x];
}
}
if(x==y) return y;
for(int k=log2;k>=0;k--) {
if(dp[k][x]&&dp[k][x]!=dp[k][y]) {
x=dp[k][x];
y=dp[k][y];
}
}
return dp[0][x];
}
int main()
{
fin>>n>>m;
for(int i=2;i<=n;i++) {
fin>>dp[0][i];
g[dp[0][i]].push_back(i);
}
dfs(1,1);
for(int i=1;(1<<i)<=n;i++) {
for(int j=1;j<=n;j++) {
dp[i][j]=dp[i-1][dp[i-1][j]];
}
}
for(int i=1;i<=m;i++) {
int x,y;
fin>>x>>y;
fout<<lca(x,y)<<'\n';
}
return 0;
}