You are right. Fixed the warning.

I have the same question. For example, along the line we must go through two letters 'A' : is it possible to go through the same letter 'A' 2 times (by crossing), and to avoid the second letter 'A' ?

No Stefano,
This is unacceptable.

The line should pass through each letter. The letter can not be remained out of the loop.

Perhaps such conditions would make the puzzle more difficult. But I assumed that the line goes through all the characters.

In the answering form, for puzzle 11, I think the answer keys need to be of length 11 not 10 as claimed by the format verification code (which warns me that my answer keys are not of the right length).

(In general, many of the answer keys seem trickier than necessary -- really, counting the C's? diagonals that go in the opposite of the usual direction? --, but it's too late to change them).

I'm a pronounced left-handed. Maybe because I offered unusual diagonals?

About puzzle 10 (APRIL CONTEST 2015 AT LMI):
It is not necessary for the line to start at cells with A and end at cells with I.

Hello. New question : in Sudoku without wall, may a wall segment separate two cells of the same area ?

Hello, certainly not!

#@!%^

????????????, ????! ??????? ?? ?????????? ???????.

4. ???????????? ??????.
????? ?????? ???????? ???????, ? ??????? ??? ??????, ????? ? ??????? ????????? ?????????? ? ???? ??? ? ?????? ?????.

1.????? ??, ??? ?????? ????? ? ??????? ?????? ???? ?? ??? ????????? ? ??????????????? ???????? ??? ??????? ?????????? ???? ? 2 ? 0, 2 ? 0 ? ?????????? ???????, ?? ?? ????????????. ????? ?? ? ???????????? ???? ???? 2 ? 5 - ??? ????????? "???????" ???????????
2. ????? ????? ?? ????? ???? ? ?????????? ?? ???????? ????????, 2 ? 5 ????? ??? ????

Zdravstvujte, Riad! Spasibo za interesnye zadanija.

4. ZAZERKAL''NYE SUDOKU.
Serym cvetom otmecheny zerkala, a zeljonym vse kletki, cifry v kotoryh zerkal'no otrazhajutsja v sebja ili v drugie cifry.

1.Verno li, chto kazhdaja cifra v zeljonoj kletke HOTJa BY RAZ otrzhaetsja v sootvetstvujushhej zeljonoj? Kak primere vnutrennie ugly s 2 i 0, 2 i 0 v zerkal'nyh zeljonyh, no ne povtorjajut'sja. Mogut li v edinstvennoj pare byt' 2 i 5 - jeto schitaetsja "zeljonym" otrazheniem?
2. Kakie cifry NE MOGUT BYT'' v zerkal'nyh NE ZELJoNYH? Naprimer, 2 i 5 mogut ili net?

Edited by Mihalich 2015-04-07 11:44 AM






Attachments
----------------
Mihalich_Post18193.png (17KB - 5 downloads)

Zdravstvujte, Vladimir!
1. Verno. Da, 2 i 5 mogut byt' v edinstvennoj pare (ne v diagonal'noj, razumeetsja).
2. Ogranichenij net: v belyh kletkah mogut vstretit'sja ljubye cifry, v tom chisle 2 i 5.

Vyhodit, 2 i 5 - jeto i zerkal'noe otrazhenie i net odnovremenno? ili tol'ko po gorizontali(vertikali)?

Mozhet li 2 byt' v zeljonoj kletke pri otrazhenii vpravo ili vniz ili tol'ko po diagonali?
3 mozhet byt' v zeljonoj kletke TOL''KO pri gorizontal'nom zerkale (vniz-vverh)?

2 zerkal'no otrazhaetsja v 5, esli rech' o sosednih po gorizontali ili vertali poljah. V sebja 2 otrazhaetsja "tol'ko po diagonali".
S 3 vsjo verno.

4 ne mozhet byt' v zeljonoj kletke - neotrazimaja zerkal'no?

Ne mozhet.

I am not able to solve even a single puzzle :(

Read the rules carefully, multiple times.
Try to find openings, applying the rules.
Try to think "If .... then what happens, is any rule violated."
And if you are stuck, save your work and come back later.

I have a little question about puzzle 10...
In the requested sentence there are two "I' 's and one time the digit 1. But it looks like there are three same characters "I" (or 1?) in the grid? Could all three characters be used for the digit 1?

1 can be any of the three "I". Two other "I" will be letters.

Just to make sure -- in "Tools", the answer key only describes whether the edges of the grid along the given row or column are occupied (and if so by what tool) or not, correct?

More precisely: what would be the answer key for the second row in the example? Am I right that it would be -----HH---- ? (i.e. the edges that are "inside" the ladder are unoccupied and so remain "-" in the answer key, even though there is a ladder) ?

Yes, for the second row in the example the answer is recorded correctly.

Just a small confirmation for #10 (April Contest 2015 At LMI):
At the points of intersection, the line path must always continue straight ahead, it cannot have 2 turns (reflecting off each other)?

The line path must always continue straight.