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#include <fstream>
#include <algorithm>
using namespace std;
ifstream cin ("lca.in");
ofstream cout ("lca.out");
const int N = 1e5;
int dp[N + 1][30], h[N + 1];
vector <int> g[N + 1];
int n, m, x, y;
void dfs (int node, int tata)
{
h[node] = h[tata] + 1;
for (auto it : g[node])
dfs (it, node);
}
int lca (int x, int y)
{
if (h[x] > h[y])
swap (x, y);
int dif = h[y] - h[x];
for (int i = 0; (1 << i) <= dif; ++i)
if ((1 << i) & dif)
y = dp[y][i];
if (x == y)
return x;
for (int i = __lg(h[x]); i >= 0; --i)
if (dp[x][i] != dp[y][i])
x = dp[x][i], y = dp[y][i];
return dp[x][0];
}
int main()
{
cin >> n >> m;
for (int i = 2; i <= n; ++i)
cin >> dp[i][0], g[dp[i][0]].push_back(i);
dfs (1, 0);
for (int i = 1; (1 << i) <= n; ++i)
for (int j = 1; j <= n; ++j)
dp[j][i] = dp[dp[j][i - 1]][i - 1];
for (int i = 1; i <= m; ++i)
{
cin >> x >> y;
cout << lca (x, y) << '\n';
}
return 0;
}