@yzfwsf,
thanks for these training puzzles.
Puzzle 1, SE 9.2
- Code: Select all
+------------------------+------------------------+-------------------------+
| 8 1 457 | 2579 279 3 | 24569 469 2-45 |
| 2 6 357 | 4 1789 1789 | 159 1-3 358 |
| 345 35 9 | 258 6 128 | 7 134 23458 |
+------------------------+------------------------+-------------------------+
| 1367 4 1238 | 2678 5 27-68 | 126 1367 9 |
| 13567 2357 1235 | 2679 27-39 4 | 8 1367 237 |
| 9 237 238 | 1 2378 2678 | 246 5 2347 |
+------------------------+------------------------+-------------------------+
| 145 8 12-45 | 269 1249 1269 | 3 479 457 |
| 347 27-39 6 | 279 2479 5 | 49 8 1 |
| 17-45 579 145 | 3 14789 1789 | 459 2 6 |
+------------------------+------------------------+-------------------------+
Second diagonal symmetry [1] [2] [7] [39] [45] [68]. The second diagonal can contain only 1, 2, 7
- Code: Select all
+------------------+------------------+-----------------+
| 8 1 47 | 5 79 3 | 6 49 2 |
| 2 6 37 | 4 8 79 | 59 1 35 |
| 45 35 ***************9 | 2 6 1 | 7 34 8 |
+------------------+------------------+-----------------+
| 6 4 23 | 8 5 27 | 1 37 9 |
| 1 35 25+3 | 9 2-7 4 | 8 6 37 |
| 9 7 8 | 1 3 6 | 2 5 4 |
+------------------+------------------+-----------------+
| 45 8 1 | 6 24+9 29 | 3 79 57 |
| 3 2 6 | 7 49 5 | 49 8 1 |
| 7 9 45 | 3 1 8 | 45 2 6 |
+------------------+------------------+-----------------+
BUG+2 (7=3)r5c9 - (3)r5c3 == (9)r7c5 - (9=7)r1c5 => -7 r5c5; ste
********************************
Puzzle 2 SE 9.2
- Code: Select all
+-----------------------+-----------------------+-----------------------+
| 6 378 378 | 345 135 2 | 3458 9 1345 |
| 34 1 2 | 345 9 8 | 345 7 6 |
| 349 389 5 | 7 136 136 | 348 134 2 |
+-----------------------+-----------------------+-----------------------+
| 237 6 1378 | 9 123578 137 | 2345 1345 1345 |
| 5 238 4 | 238 12368 136 | 9 136 7 |
| 2379 2379 1379 | 235 123567 4 | 2356 8 135 |
+-----------------------+-----------------------+-----------------------+
| 1 239 369 | 238 238 5 | 7 346 349 |
| 8 5 379 | 6 4 379 | 1 2 39 |
| 2379 4 3679 | 1 237 379 | 356 356 8 |
+-----------------------+-----------------------+-----------------------+
Central symmetry [12] [49] [57] [68]. Digit 3 must map to itself and be at the center +3 r5c5
- Code: Select all
+-----------------------+----------------------+-----------------------+
| 6 378 378 | 345 15 2 | 3458 9 1345 |
| 34 1 2 | 345 9 8 | 345 7 6 |
| 349 389 5 | 7 a16 136 | 348 34-1 2 |
+-----------------------+----------------------+-----------------------+
| 237 6 1378 | 9 12578 17 | 2345 1345 1345 |
| 5 28 4 | 28 3 16 | 9 d16 7 |
| 2379 2379 1379 | 25 b12567 4 | c2356 8 135 |
+-----------------------+----------------------+-----------------------+
| 1 239 369 | 238 28 5 | 7 346 349 |
| 8 5 379 | 6 4 379 | 1 2 39 |
| 2379 4 3679 | 1 27 379 | 356 356 8 |
+-----------------------+----------------------+-----------------------+
2. W-Wing (1=6)r3c5 - r6c5 = r6c7 - (6=1)r5c8 => -1 r3c8
- Code: Select all
+------------------+------------------+------------------+
| 6 7 *38 | 4 5 2 | *38 9 1 |
| 4 1 2 | 3 9 8 | 5 7 6 |
| 9 38 5 | 7 16 16 | 48-3 34 2 |
+------------------+------------------+------------------+
| 3 6 a18 | 9 b28+1 7 | 24 14 5 |
| 5 2-8 4 | d28 3 16 | 9 16 7 |
| 7 29 19 | 5 c16+2 4 | 26 8 3 |
+------------------+------------------+------------------+
| 1 39 69-3 | 28 28 5 | 7 36 4 |
| 8 5 7 | 6 4 3 | 1 2 9 |
| 2 4 *36 | 1 7 9 | *36 5 8 |
+------------------+------------------+------------------+
3. X-Wing (3)r19\c36 => -3 r3c7, r7c3
4. BUG+2 (8=1)r4c3 - (1)r4c5 == (2)r6c5 - (2=8)r5c4 => -8 r5c2; ste
********************************
Puzzle 3 SE 9.0
- Code: Select all
+------------------------+----------------------+---------------------+
| *8 7 5 | *2-3469 249 236 | *12-3 169 134 |
| *1 26 24 | *8 249 236 | *2-39 5 7 |
| *2-46 9 3 | *1 5 7 | *28 68 48 |
+------------------------+----------------------+---------------------+
| 34579 358 4789 | 5679 179 156 | 1358 18 2 |
| 2359 2358 6 | 259 129 4 | 1358 7 138 |
| 257 1 27 | 257 3 8 | 6 4 9 |
+------------------------+----------------------+---------------------+
| 35679 3568 789 | 3457 147 135 | 1789 2 18 |
| 2379 4 2789 | 237 6 123 | 1789 189 5 |
| 257 25 1 | 257 8 9 | 4 3 6 |
+------------------------+----------------------+---------------------+
Look at the pattern:
The number of given and solved cells in boxes, maps as follows:
- Code: Select all
| 6 | 4 | 2 |
| 2 | 3 | 5 |
| 2 | 3 | 5 |
The similarity between bands 2, 3 is a clue for a column sticks symmetry, with sticks located in band 1.
The number of givens and solved cells in columns maps as follows:
- Code: Select all
| 2 4 4 | 2 4 4 | 2 4 4 |
This gives a clue to find the sticks: in b1, r123c1; in b2, r123c4, in b3, r123c7 (the columns that have a pattern different from the other two's).
From there, no need for a prior isomorphism, the automorphism is obvious:
swap bands [23], then swap columns [23] [56] [89] (the sticks don't move)
- Code: Select all
|857|...|...|
|...|...|.75|
|.39|175|...|
|---+---+---|
|...|...|..2|
|..4|..6|.5.|
|.1.|.98|463|
|---+---+---|
|...|...|.2.|
|.6.|.4.|..7|
|..1|.83|694|
then carry out digit permutation [39] [46] [57] [1] [2] [8]. The start puzzle is recovered:
- Code: Select all
|875|...|...|
|...|...|.57|
|.93|157|...|
|---+---+---|
|...|...|..2|
|..6|..4|.7.|
|.1.|.38|649|
|---+---+---|
|...|...|.2.|
|.4.|.6.|..5|
|..1|.89|436|
The sticks can contain only the invariant digits => +2 r3c1, +2 r1c4, +2r2c7, +1 r1c7, +8r3c7; ste.
********************************
Puzzle 4 SE 9.1
- Code: Select all
+-----------------------+---------------------+-----------------------+
| 137 1478 178 | 378 9 1478 | 6 5 2 |
| 137 12478 1278 | *5 *3-14 *6 | 4789 348 14789 |
| 5 9 6 | 378 2 1478 | 478 348 1478 |
+-----------------------+---------------------+-----------------------+
| 167 1678 9 | *6-14 *5 *3 | 2 468 4678 |
| 2 67 57 | 46 8 9 | 457 1 3 |
| 4 3 158 | 16 7 2 | 58 9 68 |
+-----------------------+---------------------+-----------------------+
| 679 267 4 | *3-78 *36 *5 | 1 268 689 |
| 169 16 3 | 2 146 148 | 489 7 5 |
| 8 5 127 | 9 146 147 | 3 246 46 |
+-----------------------+---------------------+-----------------------+
Given and solved cells map (per box)
- Code: Select all
| 3 | 4 | 3 |
| 4 | 6 | 4 |
| 4 | 3 | 4 |
similar stacks [13] => possible row sticks symmetry, sticks in stack 2
Given and solved cells map (per row)
- Code: Select all
| 3 2 3 | 4 5 5 | 3 4 4 |
=> sticks r2c456, r4c456, r7c456
Prior isomorphism (I): swap circularly rows [789] [7->9], [8->7], [9->8]
- Code: Select all
|...|.9.|526|
|...|...|...|
|596|.2.|...|
|---+---+---|
|..9|.53|..2|
|2..|.89|13.|
|43.|.72|9..|
|---+---+---|
|..4|..5|..1|
|..3|2..|75.|
|85.|9..|..3|
Automorphism of the resulting puzzle:Swap stacks [13], then swap rows [13], [56], [89].The start puzzle is recovered:
- Code: Select all
|...|.2.|596|
|...|...|...|
|526|.9.|...|
|---+---+---|
|..2|.53|..9|
|9..|.72|43.|
|13.|.89|2..|
|---+---+---|
|..1|..5|..4|
|..3|9..|85.|
|75.|2..|..3|
and then carry out digit permutation [14] [29] [78] [3] [5] [6]
- Code: Select all
|...|.9.|526|
|...|...|...|
|596|.2.|...|
|---+---+---|
|..9|.53|..2|
|2..|.88|13.|
|43.|.72|9..|
|---+---+---|
|..4|..5|..1|
|..3|2..|75.|
|85.|9..|..3|
Eventually apply inverse I. The start puzzle is recovered.
- Code: Select all
|...|.9.|652|
|...|...|...|
|596|.2.|...|
|---+---+---|
|..9|.53|2..|
|2..|.88|.13|
|43.|.72|.9.|
|---+---+---|
|..4|..5|1..|
|..3|2..|.75|
|85.|9..|3..|
The sticks can contain only the invariant digits => +3 r2c3, +6 r4c4, +3r7c4, +6 r7c57; ste.