【題解】CSES 1750 Planets Queries I

#include <iostream>
using namespace std;
 
int n, q, a[200005][31], x, k;
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> q;
    for (int i = 1; i <= n; i++){
        cin >> a[i][0];
    }
    for (int i = 1; i < 31; i++){
        for (int j = 1; j <= n; j++){
            a[j][i] = a[a[j][i-1]][i-1];
        }
    }
    while (q--){
        cin >> x >> k;
        for (int i = 0; i < 31; i++){
            if (k & (1<<i)){
                x = a[x][i];
            }
        }
        cout << x << "\n";
    }
}