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#include <fstream>
#include <vector>
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int H = 200;
int n,i,x,y,m;
int nv[100005];
int tt[100005];
int ttm[100005];
bool viz[100005];
vector<int>ls[100005];
void df(int x, int tm, int niv) {
ttm[x] = tm;
if (niv%H == 0)
tm = x;
nv[x] = niv;
viz[x]=1;
int i, l = ls[x].size(), y;
for (i = 0; i<l; i++) {
if (viz[ls[x][i]] == 0)
df(ls[x][i],x,niv+1);
}
}
int query(int x, int y) {
while (ttm[x]!=ttm[y]) {
if (nv[x]>nv[y])
x = ttm[x];
else y=ttm[y];
}
while (x != y) {
if (nv[x]>nv[y])
x = tt[x];
else y=tt[y];
}
return x;
}
int main() {
f>>n>>m;
for (i = 2; i <= n; i++) {
f>>tt[i];
ls[tt[i]].push_back(i);
}
df(1,1,0);
while (m--) {
f>>x>>y;
g<<query(x,y)<<'\n';
}
return 0;
}