poj3278 Catch That Cow |bfs|队列|Java

import java.sql.Time;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

public class Main{

public static int k, n;
public static int MAXN = 100000;
public static int[] vis = new int[100005];

public static class P {
int p;
int time;

P(int x, int y) {
p = x;
time = y;
}
}

public static void bfs() {
return;
}

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
while (scanner.hasNext()) {
Arrays.fill(vis, 0);

n = scanner.nextInt();
k = scanner.nextInt();

P p = new P(n, 0);
Queue<P> q = new LinkedList<P>();
q.offer(p);
vis
= 1;
while (!q.isEmpty()) {
P t = q.poll();
if (t.p == k) {
System.out.println(t.time);
break;
} else {
if (t.p - 1 >= 0 && vis[t.p - 1] != 1) {
q.offer(new P(t.p - 1, t.time + 1));
vis[t.p - 1] = 1;
}
if (t.p + 1 <= MAXN && vis[t.p + 1] != 1) {
q.offer(new P(t.p + 1, t.time + 1));
vis[t.p + 1] = 1;
}
if (t.p * 2 <= MAXN && vis[t.p*2] != 1) {
q.offer(new P(t.p * 2, t.time + 1));
vis[t.p * 2] = 1;
}
//System.out.print(t.p*2+"=");
//System.out.println(t.time);
}
}
}
return;
}
}