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// stramosi.cpp : This file contains the 'main' function. Program execution begins and ends there.
//
//#include "pch.h"
#include <iostream>
#include <fstream>
#include <cmath>
#include <vector>
#define NMAX 250001
using namespace std;
class Solver {
public:
explicit Solver(istream&& in, ostream&& out) {
int Q;
vector <int> ancestors;
// read data
in >> N >> Q;
// resize the vector so that it have enough space for all numbers
ancestors.resize(N + 1);
for (int i = 1; i <= N; ++i) {
in >> ancestors[i];
}
// do the dynamic programming magic :))
__process(ancestors);
// answer the questions
int P, X;
while (Q--) {
in >> X >> P;
out << __solve(X, P) << '\n';
}
}
private:
int __lg(int number) const {
return floor(log2(number));
}
void __process(const vector<int>& ancestors) {
/*
S[i][j] = the 2 ^ j ancestor of node i
S[i][0] = ancestors[i]
S[i][j] = S[S[i][j-1]][j-1] while S[i][j - 1] != 0
*/
for (int i = 1; i <= N; ++i) {
// first ancestor is the father
S[i][0] = ancestors[i];
// calculate the second, the forth, ..., ancestor of node i as long as it exists
for (int j = 1; j <= __lg(N); ++j) {
if (!S[i][j - 1]) {
break;
}
S[i][j] = S[S[i][j - 1]][j - 1];
}
}
}
int __solve(int Q, int P) {
if (__lg(P) > __lg(N)) {
return 0;
}
// if P is power of 2 then the answer is calculated in the matrix
int value = __lg(P);
if ((1 << value) == P) {
return S[Q][value];
}
// calculate the nth ancestor
int power = __lg(P), ancestor;
for (; P != 0; power = __lg(P)) {
ancestor = S[Q][power];
if (!ancestor) {
break;
}
P -= (1 << power), Q = ancestor;
}
return ancestor;
}
int N, S[NMAX][18];
} solver{
ifstream{"stramosi.in"},
ofstream{"stramosi.out"}
};
int main() {
return 0;
}