注意输入的方式

import java.math.*;
import java.util.*;
import java.io.*;

public class Main {
    static BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
    static PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

    public static void main(String[] args) throws IOException {
        Solution s = new Solution();

        s.solve(read, out);
    }
}

class Solution{
    public Solution(){}
    static int N = (int)1e5 + 3;
    int[] d = new int[N];
    int n, k;
    int[] dx = {-1, 1};

    int bfs() {
        Arrays.fill(d, -1);
        Queue<Integer> q = new ArrayDeque<>();
        d[n] = 0;
        q.add(n);

        while (!q.isEmpty()) {
            int p = q.remove();
            int x = 0;
            for (int i = 0; i < 3; i++) {
                if (i == 2) {
                    x = p * 2;
                    if (x >= 1 && x < N && d[x] == -1) {
                        d[x] = d[p] + 1;
                        q.add(x);
                    }
                }else {
                    x = p + dx[i];
                    if (x >= 1 && x < N && d[x] == -1) {
                        d[x] = d[p] + 1;
                        q.add(x);
                    }
                }
            }
        }
        return d[k];
    }

    public void solve (BufferedReader read, PrintWriter out) throws IOException {
        String s;
        while ((s = read.readLine()) != null) {
            String[] ss = s.split(" ");
            n = Integer.valueOf(ss[0]);
            k = Integer.valueOf(ss[1]);
            out.println(bfs());
        }
        out.flush();
    }
}

class Test{
    public Test(){};

    public void test () {

    }
}