Cod sursa(job #2624800)

Utilizator nicu_ducalNicu Ducal nicu_ducal Data 5 iunie 2020 13:45:33
Problema Stramosi Scor 80
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.53 kb
#include <bits/stdc++.h>
#define debug(x) cerr << #x << " = " << x << "\n"
#define all(x) (x).begin(),(x).end()
#define sqr(x) (x) * (x)
#define len length()
#define sz size()
#define pb push_back
#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<ll,ll>

using ull = unsigned long long;
using ll = long long;
using namespace std;
 
template <typename T>
ostream& operator<<(ostream &os, const vector<T> &v) { os << '{'; string sep; for (const auto &x : v) os << sep << x, sep = ", "; return os << '}'; }
template <typename A, typename B>
ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
 
const int INF = INT_MAX, maxK = 22;
ll t, n, q, p, m;
vector<vector<int>> dp; 

 
int query(int nod, int k) {
	int temp = 0;
	while (k > 0) {
		temp = log2(k);
		// cout << temp << " " << nod << " " << dp[nod][temp] << "\n";
		nod = dp[nod][temp];
		if (nod == 0)
			return 0;
		k -= (1 << temp);
	}
	return nod;
}
 
int main(){
    ios_base::sync_with_stdio(0); cin.tie(); cout.tie();
    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
    ifstream cin("stramosi.in");
    ofstream cout("stramosi.out");
	
	cin >> n >> m;
	dp.resize(n + 1);
	for (int i = 0; i <= n; i++) {
		dp[i].resize(maxK + 1, 0);
	}
	
	for (int i = 1; i <= n; i++) {
		cin >> dp[i][0];
	}
	
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= maxK; j++) {
			dp[i][j] = dp[dp[i][j - 1]][j - 1];
		}
	}
	
	while (m--) {
		cin >> q >> p;
		cout << query(q, p) << "\n";
	}
	
 
    return 0;
}