## Chain exercise.

Post the puzzle or solving technique that's causing you trouble and someone will help

### Chain exercise.

This might serve as an exercise in chain application:
Code: Select all
` . . 9 | . 4 . | 7 . .  . . . | . . . | . . .  4 . . | 1 . 3 | . . 6 -------+-------+------  . . 3 | 8 . 7 | 4 . .  2 . . | . . . | . . 1  . . 8 | 4 . 2 | 6 . . -------+-------+------  9 . . | 2 . 6 | . . 3  . . . | . . . | . . .  . . 7 | . 8 . | 5 . .`

[Edit: It was not as hard as I thought. Needed one step with bilocation chains, and a later step with mixed xy-chains. So, I don't need 'help' any longer, but leaves the puzzle as an exercise.]
Last edited by Ocean on Sat Apr 15, 2006 11:15 am, edited 1 time in total.
Ocean

Posts: 442
Joined: 29 August 2005

### Looks tough to me

I would rate any puzzle that starts with three swordfish as challenging!

Keith
keith
2017 Supporter

Posts: 215
Joined: 03 April 2006

After the 2 swordfishes:

Code: Select all
` *-----------------------------------------------------------------------------* | 13568   12356   9       | 56      4       58      | 7       1235    258     | | 135678  1356    1256    | 5679    2569    589     | 1239    13459   4589    | | 4       578     25      | 1       2579    3       | 289     589     6       | |-------------------------+-------------------------+-------------------------| | 156     1569    3       | 8       1569    7       | 4       259     259     | | 2       45679   456     | 3569    3569    59      | 389     35789   1       | | 157     159     8       | 4       1359    2       | 6       359     579     | |-------------------------+-------------------------+-------------------------| | 9       1458    145     | 2       57      6       | 18      1478    3       | | 13568   13456   12456   | 3579    359     14      | 129     1469    4789    | | 136     12346   7       | 39      8       14      | 5       12469   249     | *-----------------------------------------------------------------------------*`

If r2c4=7:
r3c2=7,r7c2=8
r8c9=7,r8c1=8
=> r2c1=7

Code: Select all
` *--------------------------------------------------------------------* | 1356   12356  9      | 56     4      58     | 7      125    258    | | 7      156    56     | 569    2      589    | 13     1345   458    | | 4      8      25     | 1      7      3      | 29     59     6      | |----------------------+----------------------+----------------------| | 156    1569   3      | 8      19     7      | 4      259    259    | | 2      7      4      | 359    6      59     | 39     8      1      | | 15     159    8      | 4      139    2      | 6      359    7      | |----------------------+----------------------+----------------------| | 9      4      1      | 2      5      6      | 8      7      3      | | 8      356    256    | 7      39     14     | 129    1469   49     | | 36     236    7      | 39     8      14     | 5      12469  249    | *--------------------------------------------------------------------*`

If r6c5=3:
r8c5=9
r2c8=3,r2c9=4,r8c9=9
=> r6c8=3

PS: Sorry, i have not seen before, that Ocean already posted essentially the same solution in another thread yesterday.
ravel

Posts: 998
Joined: 21 February 2006

ravel wrote:If r2c4=7:
r3c2=7,r7c2=8
r8c9=7,r8c1=8
=> r2c1=7

If r6c5=3:
r8c5=9
r2c8=3,r2c9=4,r8c9=9
=> r6c8=3

PS: Sorry, i have not seen before, that Ocean already posted essentially the same solution in another thread yesterday.

Thank you for showing your solution. The fact that our methods are essentially the same, might indicate that this is the most natural way to solve the two hard steps.
Ocean

Posts: 442
Joined: 29 August 2005

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