Submission #27363241

---

Source Code Expand

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.stream.Stream;

public class Main {

  public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String[] head = br.readLine().split(" ");
    int n = Integer.parseInt(head[0]);
    int x = Integer.parseInt(head[1]) - 1;
    int[] array = Stream.of(br.readLine().split(" ")).mapToInt(value -> Integer.parseInt(value) - 1)
        .toArray();
    br.close();
    boolean[] isUsed = new boolean[n];
    Arrays.fill(isUsed, false);
    int ans = 0;
    int idx = x;
    while (!isUsed[idx]) {
      isUsed[idx] = true;
      ans += 1;
      idx = array[idx];
    }
    System.out.println(ans);
  }
}

Submission Info

Judge Result