Cod sursa(job #1695378)

Utilizator al.mocanuAlexandru Mocanu al.mocanu Data 26 aprilie 2016 23:14:20
Problema Stramosi Scor 90
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.58 kb
#include <stdio.h>
#include <vector>
using namespace std;

const int MAX = 250005;
int n, m, x, y, p[MAX][19];

int anc(int x, int y){
	int pow = 0;
	for(int i = 0; (1<<i) <= y; i++)
		if(y & (1<<i))
			x = p[x][i];
	return x;
}

int main(){
	freopen("stramosi.in", "r", stdin);
	freopen("stramosi.out", "w", stdout);
	scanf("%d%d", &n, &m);
	for(int i = 1; i <= n; i++)
		scanf("%d", &p[i][0]);

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

	for(int i = 0; i < m; i++){
		scanf("%d%d", &x, &y);
		printf("%d\n", anc(x, y));
	}
	return 0;
}