Cod sursa(job #2890133)

Utilizator matthriscuMatt . matthriscu Data 14 aprilie 2022 17:28:41
Problema Stramosi Scor 80
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.64 kb
#include <bits/stdc++.h>
using namespace std;

vector<vector<int>> dp(250005, vector<int>(20, 0));

int main()
{
	ifstream fin("stramosi.in");
	ofstream fout("stramosi.out");

	int n, m;
	fin >> n >> m;

	vector<int> log(n + 1);
	log[1] = 0;
	for (int i = 2; i <= n; ++i)
		log[i] = log[i / 2] + 1;

	for (int i = 1; i <= n; ++i)
		fin >> dp[i][0];

	for (int i = 1; i <= n; ++i)
		for (int j = 1; j <= log[n]; ++j)
			dp[i][j] = dp[dp[i][j - 1]][j - 1];

	while (m--) {
		int p, q;
		fin >> q >> p;

		int ans = 0, pow;
		for (pow = 1; pow <= p; pow <<= 1);
		for (; pow; pow >>= 1)
			if (p & pow)
				ans = q = dp[q][log[pow]];

		fout << ans << '\n';
	}
}