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#include<bits/stdc++.h>
#define N 1030
using namespace std;
int n,m,lvl[N], dp[N][30];
vector<int>V[N];
void DFS(int x, int h) {
lvl[x]=h;
for (auto it:V[x]) {
DFS(it, h+1);
}
}
int main() {
ifstream cin("lca.in");
ofstream cout("lca.out");
cin>>n>>m;
for (int i=2; i<=n; i++) {
int x; cin>>x;
dp[i][0]=x;
V[x].push_back(i);
}
for (int i=2; i<=n; i++) {
for (int j=1; (1<<j)<=n; j++) {
dp[i][j] = dp[dp[i][j-1]][j-1];
}
}
DFS(1,0);
while (m--) {
int x,y, p=0; cin>>x>>y;
while (lvl[x]!=lvl[y]) {
if (lvl[x]<lvl[y]) swap(x,y);
p=0;
while (dp[x][p+1] && lvl[dp[x][p+1]]>=lvl[y]) p++;
x = dp[x][p];
}
while (x!=y) {
p=0;
while (dp[x][p+1]!=dp[y][p+1]) p++;
x=dp[x][p];
y=dp[y][p];
}
cout<<x<<'\n';
}
return 0;
}