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I propose this newly created Hidoku puzzle (for a manual solution !)
.---------------------------.
7 | __ __ __ 01 __ __ __|
6 | __ 19 __ __ __ 42 __|
5 | __ __ __ 31 __ __ __|
4 | __ 22 __ 30 __ __ __|
3 | __ __ __ __ 35 __ 12|
2 | __ __ __ __ __ __ __|
1 | __ __ __ 49 08 __ __|
'---------------------------'
a b c d e f g
Update 1 (Sept 13, 2026)
This puzzle has a very tough beginning, but after working
hard in the first move, placing a key number, only easy
deductions are needed afterwards !
Some hints for the key move 1:
. study important connections, like 01-08, 12-19, etc, and the
possible paths for each connection.
. special attention to unique passages is very important, like
f3, d3-f4, c4, and a few others.
. In summary: global view is better here than local considerations.
Update 2 (September 14, 2026)
.---------------------------.
7 | __ __ __ 01 __ __ __|
6 | __ 19 __ __ __ 42 __|
5 | __ __ __ 31 __ __ __|
4 | __ 22 __ 30 __ __ __|
3 | __ __ __ __ 35 __ 12|
2 | __ __ __ __ __ __ __|
1 | __ __ __ 49 08 __ __|
'---------------------------'
a b c d e f g
For move 1 we consider the following possibilities:
I.1 42-49 takes d3,e4
/
I. 01-08 takes c4
\
I.2 42-49 takes e2,f3
II.1 42-49 passes by c4,e6, and disconnects 12-19!
/
II. 01-08 takes f3 II.2.1 12-19 uses c4 [quick trouble!]
\ /
II.2 42-49 takes e3,f4
\
II.2.2 12-19 uses c6 [quick trouble!]
III.1 42-49 takes c4,c6 -> disconnect 12-19!
/
III. 01-08(x) takes d3,e4
\
III.2 42-49(y) takes e2,f3 and also f4 or g4.
while 12-19(z) must use one of f4 or g4.
Then, 35-42(w) must go through d2, c4, e6,
disconnecting 12-19 [see below]
.---------------------------.
7 | __ __ __ 01 __ __ __|
6 | __ 19 __ w_ __ 42 __|
5 | __ __ __ 31 __ __ __|
4 | __ 22 w_ 30 x_ yz yz|
3 | __ __ __ x_ 35 y_ 12|
2 | __ __ __ w_ y_ __ __|
1 | __ __ __ 49 08 __ __|
'---------------------------'
a b c d e f g
Apart from III.2 (shown above), we show the details of I.1 below:
42-49(y) takes d3,e4 then 12-19(z) must pass through d6,
and through f4 or f5. But 31-35(w) must pass through f4 or f5.
So f4,f5 is locked to those paths(zw). Also, one of 35-42(v),
31-35(w) must use cell f3. This forces 42-49(y) to use cell
e5, and 31-35(w) must use e6. Now 12-19 is disconnected!
.---------------------------.
7 | __ __ __ 01 __ __ __|
6 | __ 19 __ z_ w_ 42 __|
5 | __ __ __ 31 y_ zw __|
4 | __ 22 x_ 30 y_ vzw __|
3 | __ __ __ y_ 35 vw 12|
2 | __ __ __ __ __ __ __|
1 | __ __ __ 49 08 __ __|
'---------------------------'
a b c d e f g
From this long analysis, we conclude
1.(02)c6!!! with 12 additional placements
we get
.---------------------------.
7 |*18 *17 *16 01 __ __ __|
6 |*20 19 *02 *15 __ 42 __|
5 |*21 *03 __ 31 *14 __ __|
4 |*04 22 __ 30 __ *13 __|
3 | __ *05 __ __ 35 __ 12|
2 | __ __ __ *07 __ __ __|
1 | __ __ __ 49 08 __ __|
'---------------------------'
a b c d e f g
How to continue ?
Update 3 (Sept 15, 2026)
Part 2: 35-42(x) and 42-49(y)
must use, each, one of the passages
[e4](XX), and [f3,g4](YY).
So 11, must be at Row 2 and
06
.---------------------------.
7 |*18 *17 *16 01 __ __ __|
6 |*20 19 *02 *15 __ 42 __|
5 |*21 *03 __ 31 *14 __ __|
4 |*04 22 __ 30 XX *13 YY|
3 | __ *05 __ __ 35 YY 12|
2 | __ __ __ *07 __ __ __|11
1 | __ __ __ 49 08 __ __|
'---------------------------'
a b c d e f g
14.(32)c5!!
After this the remaining moves
are easily found.
The final configuration is
.---------------------------.
7 |*18 *17 *16 01 *39 *40 *41|
6 |*20 19 *02 *15 *38 42 *43|
5 |*21 *03 *32 31 *14 *37 *44|
4 |*04 22 *33 30 *36 *13 *45|
3 |*23 *05 *29 *34 35 *46 12|
2 |*24 *28 *06 *07 *48 *47 *11|
1 |*25 *26 *27 49 08 *09 *10|
'---------------------------'
a b c d e f g
Created: February 12, 2024
Contact: sudo.jco.br@gmail.com