Difference between revisions of "Ladder puzzle 1/Solution"

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(Explained the correct solution)
(Wrong: f6: maybe not so wrong at all)
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Finally, Red plays a double threat. This stone is the ladder helper, and it also threatens to connect along the top.
 
Finally, Red plays a double threat. This stone is the ladder helper, and it also threatens to connect along the top.
  
== Wrong: f6 ==
+
== Alternative Solution: f6 ==
  
 
<hex>R8 C8 Q1 Vc6 Vd5 Vd4 Ve3 Vh4 Hd6 Hb8 Hc1 He4 Hg3 N:on Vf6 He7</hex>
 
<hex>R8 C8 Q1 Vc6 Vd5 Vd4 Ve3 Vh4 Hd6 Hb8 Hc1 He4 Hg3 N:on Vf6 He7</hex>
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The stone at f6 is a ladder breaker for the ladder starting at c7, and it also threatens to connect via f5.
 
The stone at f6 is a ladder breaker for the ladder starting at c7, and it also threatens to connect via f5.
 
This looks very strong, but Blue can still defend at e7, which is a ladder breaker and threatens a connection at the lower side.
 
This looks very strong, but Blue can still defend at e7, which is a ladder breaker and threatens a connection at the lower side.
Since Blue has another threat at e5, this is enough for winning.
+
 
 +
<hex>R8 C8 Q1 Vc6 Vd5 Vd4 Ve3 Vh4 Hd6 Hb8 Hc1 He4 Hg3 Vf6 He7 V3g6 H4f7 V5g7 H6e6</hex>
 +
 
 +
Now Red pushes to the right, making both f4 and f6 winning points. Blue cannot defend both.
  
 
[[category:ladder puzzle]]
 
[[category:ladder puzzle]]

Revision as of 13:56, 16 February 2009

Correct: e5

abcdefgh123456781

Red's main threat is the ladder starting at c7. If Red plays out this ladder, Blue can block it. So Red needs a helping stone somewhere on the right and on the second line from the bottom. R1 threatens the follow-up moves at *, which Blue must defend.

abcdefgh12345678132

Red continues that way, using the stone at the right. Again, Blue has to defend.

abcdefgh1234567813245

Finally, Red plays a double threat. This stone is the ladder helper, and it also threatens to connect along the top.

Alternative Solution: f6

abcdefgh1234567812

The stone at f6 is a ladder breaker for the ladder starting at c7, and it also threatens to connect via f5. This looks very strong, but Blue can still defend at e7, which is a ladder breaker and threatens a connection at the lower side.

abcdefgh123456786345

Now Red pushes to the right, making both f4 and f6 winning points. Blue cannot defend both.