Poj Solution 3278

http://poj.org/problem?id=3278

import java.io.BufferedInputStream;   
import java.util.LinkedList;   
import java.util.Scanner;   
  
public class Main {   
  
    public static final int MAX = 200000;   
  
    public static void main(String[] args) {   
  
        Scanner scan = new Scanner(new BufferedInputStream(System.in));   
        if (scan.hasNext()) {   
            int n = scan.nextInt();   
            int k = scan.nextInt();   
            System.out.println(catchTheCow(n, k));   
        }   
    }   
  
    public static int catchTheCow(int n, int k) {   
        if (n == k) {   
            return 0;   
        }   
        LinkedList<Integer> queue = new LinkedList();   
        boolean[] visited = new boolean[MAX + 5];   
        int[] minutes = new int[MAX + 5];   
        visited[n] = true;   
        queue.add(n);   
        while (!queue.isEmpty()) {   
            int current = queue.removeFirst();   
            for (int i = 0; i < 3; i++) {   
                int next = current;   
                if (i == 0) {   
                    next++;   
                } else if (i == 1) {   
                    next--;   
                } else if (i == 2) {   
                    next <<= 1;   
                }   
                if (next < 0 || next > MAX) {   
                    continue;   
                }   
                if (!visited[next]) {   
                    queue.add(next);   
                    visited[next] = true;   
                    minutes[next] = minutes[current] + 1;   
                }   
                if (next == k) {   
                    return minutes[k];   
                }   
            }   
        }   
  
        return 0;   
    }   
}  
											
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