2015
02-21

# Gem Combining

In the game "Gem Craft", we create gems in the item bar.
There are N grids in the item bar, each grid can only accomodate one gem.
Each gem has its level.
When the level of a gem upgrade by 1, the power of the gem will be doubled.
The key to win the game is to get a high level gem.
Gems with level 0 are available directly.
To get gems with higher level, the only way is to combine low level gems.
Suppose we have 2*N gems with level K now, they can be turned into N gems with level (K+1) afert a combining operation.
Your task is to get at least one gem with level M in minimum steps of operation.
For one step of operation, you can do one of the following two things:
(1) Get gems with level 0 directly, filling up the empty grids.
(2) Combine even number of gems with same level.

The input contain some test cases.
Each test case contains two integers N and M (1<=N<=36, 0<=M<=20).
The input ends when N=M=0, this test case doesn’t need processing.

The input contain some test cases.
Each test case contains two integers N and M (1<=N<=36, 0<=M<=20).
The input ends when N=M=0, this test case doesn’t need processing.

4 3
8 3
0 0

9
4

HintWe use dots to present empty grid, use number to present the level of a gem.

The first sample can be solved like this:

****        Initial
0000        Get level 0 gems
**11        Combine level 0 gems
***2        Combine level 1 gems
0002        Get level 0 gems
*012        Combine level 0 gems
0012        Get level 0 gems
*112        Combine level 0 gems
**22        Combine level 1 gems
***3        Combine level 2 gems

In total of 9 steps of operation.

The second sample can be solved like this:

********        Initial
00000000        Get level 0 gems
****1111        Combine level 0 gems
******22        Combine level 1 gems
*******3        Combine level 2 gems

It only takes 4 steps of operation.


1. 第2题，TCP不支持多播，多播和广播仅应用于UDP。所以B选项是不对的。第2题，TCP不支持多播，多播和广播仅应用于UDP。所以B选项是不对的。

2. 第2题，TCP不支持多播，多播和广播仅应用于UDP。所以B选项是不对的。第2题，TCP不支持多播，多播和广播仅应用于UDP。所以B选项是不对的。