### Author Topic: 每周一题: 再分巧克力 (6/28/2004-7/4/2004)  (Read 18880 times)

#### 万精油

• Hero Member
• Posts: 1831
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« on: 六月 27, 2004, 11:42:53 pm »

#### packman

• Full Member
• Posts: 226
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #1 on: 六月 29, 2004, 11:35:55 am »
if M (or N) = 1, just pick the one next to the "bad bottom-left corner" piece, that leaves the bad corner only for your friend.

if M > 1 and N > 1, just pick the upper-right piece next to it. (i.e., if the coordinate of the bad one is (0,0), then pick (1,1)), that leaves 3 pieces including the bad one to your friend....

#### 万精油

• Hero Member
• Posts: 1831
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #2 on: 六月 29, 2004, 12:36:50 pm »

If the original is 2 x 3,  after your pick, it will have the following shape left

X
X X X

your opponent will pick the right most one, you will be left with

X
X X

and you will lose no matter what

#### packman

• Full Member
• Posts: 226
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #3 on: 六月 29, 2004, 12:40:51 pm »
You said:

So, if the original is 2x3, after my pick, it will become
x
xx,

not
x
xxx

all the pieces on the "RIGHT" side are all gone too, right?

Quote from: 万精油

If the original is 2 x 3,  after your pick, it will have the following shape left

X
X X X

your opponent will pick the right most one, you will be left with

X
X X

and you will lose no matter what

#### 万精油

• Hero Member
• Posts: 1831
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #4 on: 六月 29, 2004, 01:00:03 pm »
May be I was not clear. When I said on the right and above, I do mean AND. i.e. pieces that are both on the right side (including its own column) and above it (including its own row). If we use coordinate system, suppose the small rectangle you pick is (a,b), then, all (and only) those with  x>=a AND y>=b will be take off.

#### 七把叉

• Jr. Member
• Posts: 27
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #5 on: 六月 29, 2004, 01:02:39 pm »
packman理解错了，但也要怪万教授的表述有歧义。

#### Heng

• Newbie
• Posts: 3
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #6 on: 六月 29, 2004, 01:06:13 pm »
I think packman had a nice try. His way (takeing (1,1)) can work when M>2 and N>2, and when M=2 and N=2, at least to me.

When M=2 and N>2, such as 2X3, take (2,3). Would that work?

#### packman

• Full Member
• Posts: 226
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #7 on: 六月 29, 2004, 01:07:22 pm »
Yes, that is how I interpret it too: right AND above.
After I pick "o", all the "y"s and "o" are gone, right?

yyyyyyyy
xoyyyyyy
xxyyyyyy

Quote from: 万精油
May be I was not clear. When I said on the right and above, I do mean AND. i.e. pieces that are both on the right side (including its own column) and above it (including its own row). If we use coordinate system, suppose the small rectangle you pick is (a,b), then, all (and only) those with  x>=a AND y>=b will be take off.

#### packman

• Full Member
• Posts: 226
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #8 on: 六月 29, 2004, 01:08:48 pm »
Sorry, I mis-interpretted. Forget about my previous post.

Quote from: packman
Yes, that is how I interpret it too: right AND above.
After I pick "o", all the "y"s and "o" are gone, right?

yyyyyyyy
xoyyyyyy
xxyyyyyy

Quote from: 万精油
May be I was not clear. When I said on the right and above, I do mean AND. i.e. pieces that are both on the right side (including its own column) and above it (including its own row). If we use coordinate system, suppose the small rectangle you pick is (a,b), then, all (and only) those with  x>=a AND y>=b will be take off.

#### 七把叉

• Jr. Member
• Posts: 27
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #9 on: 六月 29, 2004, 01:22:09 pm »
packman的误解是有道理的。万教授的问题出在他是用自然语言表述

#### packman

• Full Member
• Posts: 226
##### 每周一题: 再分巧克力 (6/28/2004-7/4/2004)
« Reply #10 on: 六月 29, 2004, 01:43:58 pm »

javascript:emoticon(':lol:')javascript:emoticon(':lol:')

Quote from: 七把叉
packman的误解是有道理的。万教授的问题出在他是用自然语言表述