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#include <bits/stdc++.h>
using namespace std;
class InParser
{
private:
FILE *fin;
char *buff;
int sp;
char read_ch()
{
++sp;
if (sp == 4096)
{
sp = 0;
fread(buff, 1, 4096, fin);
}
return buff[sp];
}
public:
InParser(const char *nume)
{
fin = fopen(nume, "r");
buff = new char[4096]();
sp = 4095;
}
InParser &operator>>(int &n)
{
char c;
while (!isdigit(c = read_ch()) && c != '-');
int sgn = 1;
if (c == '-')
{
n = 0;
sgn = -1;
}
else
{
n = c - '0';
}
while (isdigit(c = read_ch()))
{
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
InParser &operator>>(long long &n)
{
char c;
n = 0;
while (!isdigit(c = read_ch()) && c != '-');
long long sgn = 1;
if (c == '-')
{
n = 0;
sgn = -1;
}
else
{
n = c - '0';
}
while (isdigit(c = read_ch()))
{
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
};
class OutParser {
private:
FILE *fout;
char *buff;
int sp;
void write_ch(char ch) {
if (sp == 50000) {
fwrite(buff, 1, 50000, fout);
sp = 0;
buff[sp++] = ch;
} else {
buff[sp++] = ch;
}
}
public:
OutParser(const char* name) {
fout = fopen(name, "w");
buff = new char[50000]();
sp = 0;
}
~OutParser() {
fwrite(buff, 1, sp, fout);
fclose(fout);
}
OutParser& operator << (int vu32) {
if (vu32 <= 9) {
write_ch(vu32 + '0');
} else {
(*this) << (vu32 / 10);
write_ch(vu32 % 10 + '0');
}
return *this;
}
OutParser& operator << (long long vu64) {
if (vu64 <= 9) {
write_ch(vu64 + '0');
} else {
(*this) << (vu64 / 10);
write_ch(vu64 % 10 + '0');
}
return *this;
}
OutParser& operator << (char ch) {
write_ch(ch);
return *this;
}
OutParser& operator << (const char *ch) {
while (*ch) {
write_ch(*ch);
++ch;
}
return *this;
}
};
InParser fin("lca.in");
OutParser fout("lca.out");
const int NMAX = 1e5 + 7;
vector<vector<int>> v(NMAX);
int dad[NMAX], lvl[NMAX];
void dfs(int nod, int lv)
{
lvl[nod] = lv;
for (int i: v[nod])
{
dfs(i, lv + 1);
}
}
int lca(int x, int y)
{
if (lvl[x] < lvl[y])
swap(x, y);
while (lvl[x] > lvl[y])
x = dad[x];
while (x != y)
y = dad[y], x = dad[x];
return x;
}
int main()
{
int n, q;
fin >> n >> q;
for (int nod = 2; nod <= n; nod++)
{
fin >> dad[nod];
v[dad[nod]].push_back(nod);
}
dfs(1, 1);
while (q--)
{
int x, y;
fin >> x >> y;
fout << lca(x, y) << "\n";
}
return 0;
}