#include <cstdio>
#include <cstring>
#include <vector>
#include <cctype>
#include <algorithm>

using namespace std;

const int maxN = 100000;
const int SIZE = 1000000;

class ReadStream {
private:
  FILE* stream;
  int pos;
  char buffer[SIZE + 1];
  void move() {
    ++ this->pos;
    if (this->pos == SIZE) {
      this->pos = 0;
      int readSize = fread(this->buffer, SIZE, 1, this->stream);
    }
  }
public:
  ReadStream(const char *fname) {
    this->stream = fopen(fname, "r");
    this->pos = 0;
    fread(buffer, SIZE, 1, stream);
  }

  ReadStream& operator >> (int &answer) {
    char sign = '+';
    while (!isdigit(this->buffer[this->pos])) {
      sign = buffer[pos];
      move();
    }

    answer = 0;
    while(isdigit(this->buffer[this->pos])) {
      answer = answer * 10 + (this->buffer[this->pos] - '0');
      move();
    }
    if(sign == '-')
      answer = -answer;
    return *this;
  }

  ReadStream& operator >> (char& c) {
    c = this->buffer[this->pos];
    move();
  }

  void close() {
    fclose(stream);
  }
};

int N;
bool viz[1 + maxN];
vector<int> sons[1 + maxN];

int id[1 + maxN], ac;
int euler[maxN << 1], where[1 + maxN], e;

int rmq[20][maxN << 1];
int Log[(maxN << 1) + 1];

void rmqCompute(int v[], int N) {
  for(int i = 0; i < N; ++ i)
    rmq[0][i] = v[i];
  for(int i = 1; (1 << i) <= N; ++ i)
    Log[(1 << i)] = 1;
  for(int i = 1; i <= N; ++ i)
    Log[i] += Log[i - 1];

  int p = 2;
  for(int step = 1; p <= N; ++ step, p <<= 1) {
    int put = p >> 1;
    for(int i = 0; i + put < N; ++ i)
      rmq[step][i] = min(rmq[step - 1][i], rmq[step - 1][i + put]);
  }
}

int rmQuery(int x, int y) {
  int l = y - x + 1;
  int step = Log[l];
  return min(rmq[step][x], rmq[step][y - (1 << step) + 1]);
}


void dfs(int node = 1) {
  if(!viz[node]) {
    viz[node] = true;
    int nodeAc = ac;
    id[ac ++] = node;
    where[node] = e;
    euler[e ++] = nodeAc;
    for (int son: sons[node]) {
      dfs(son);
      euler[e ++] = nodeAc;
    }
  }
}

int lca(int x, int y) {
  x = where[x];
  y = where[y];
  return id[rmQuery(min(x, y), max(x, y))];
}

int main() {
  ReadStream in("lca.in");
  freopen("lca.out", "w", stdout);
  int M;
  in >> N >> M;
  for(int i = 2; i <= N; ++ i) {
    int fatherI;
    in >> fatherI;
    sons[fatherI].push_back(i);
  }

  in.close();
  dfs();
  rmqCompute(euler, e);

  while(M --) {
    int x, y;
    in >> x >> y;
    printf("%d\n", lca(x, y));
  }
  return 0;
}