Printable Puzzles by KrazyDad - Free Printable

Let’s solve this Sudoku puzzle step by step.

Sudoku rules:
- Each row must have numbers 1 to 9, no repeats.
- Each column must have numbers 1 to 9, no repeats.
- Each 3x3 box (there are 9 of them) must have numbers 1 to 9, no repeats.

We’ll fill in the blanks one at a time, using logic.

---

Start with Row 1:
`3 _ _ | 6 1 _ | _ _ 8`

Missing numbers: 2,4,5,7,9

Look at Column 2: has 2,5,7 → so can’t put those in Row1-Col2? Wait — let’s check what’s already in Row1-Col2’s column and box.

Actually, better to look for cells with only one possible number.

Let’s try Box 1 (top-left 3x3):

Box 1 contains:
Row1: 3, ?, ?
Row2: ?, ?, 2
Row3: ?, ?, ?

Known numbers in Box 1: 3, 2 → missing: 1,4,5,6,7,8,9

But wait — we know from Row1 that 6 and 1 are in Row1 but outside Box1 → so they’re not in Box1. So Box1 cannot have 6 or 1 again.

Wait — actually, Row1 has 6 and 1 in Columns 4 and 5 → which are in Box2 → so Box1 doesn’t have 6 or 1 yet? No — Box1 is columns 1-3, rows 1-3.

So in Box1, current knowns:

Row1 Col1 = 3
Row2 Col3 = 2
That’s it.

Now look at Row3: `_ _ _ | 7 5 _ | 2 9 _`

In Row3, we have 7,5,2,9 → missing: 1,3,4,6,8

But 3 is already in Row1-Col1 → same column? Row3-Col1 is same column as Row1-Col1 → so Row3-Col1 cannot be 3.

Also, Box1 already has 3 → so Row3-Col1,2,3 cannot be 3.

Similarly, 2 is in Row2-Col3 → so Row3-Col3 cannot be 2 (already used).

This is getting messy. Let’s try a different approach — find easy fills.

Look at Row 5: `4 _ | 1 7 3 | _ 5 _`

Missing: 2,6,8,9

Check Column 2: values present? Let’s list Column 2:

Row1: ?
Row2: ?
Row3: ?
Row4: ?
Row5: ?
Row6: 5
Row7: ?
Row8: 2
Row9: ?

From grid:

Col2:
R1: blank
R2: blank
R3: blank
R4: blank
R5: blank
R6: 5
R7: 7
R8: 5 ← wait, R8-Col2 is 5? But R6-Col2 is also 5? That can’t be!

Wait — let me re-read the grid carefully.

Original grid:

Row1: 3 _ _ | 6 1 _ | _ _ 8
Row2: _ _ 2 | _ 3 _ | 7 6 _
Row3: _ _ _ | 7 5 _ | 2 9 _
Row4: _ 9 _ | 8 _ _ | _ 1 _
Row5: 4 _ | 1 7 3 | _ 5 _
Row6: 5 _ _ | _ 9 _ | _ 2 _
Row7: _ 3 7 | _ 4 1 | _ _ _
Row8: _ 2 5 | _ 8 _ | 9 _ _
Row9: 4 _ _ | _ 9 7 | _ _ 2

Ah! I misread earlier. In Row8, Col2 is 2, not 5. Row6-Col2 is blank. Row7-Col2 is 3. Row8-Col2 is 2. Row9-Col2 is blank.

So Column 2:

R1: ?
R2: ?
R3: ?
R4: 9
R5: ?
R6: ?
R7: 3
R8: 2
R9: ?

So known in Col2: 9,3,2 → missing: 1,4,5,6,7,8

Back to Row5: `4 _ | 1 7 3 | _ 5 _`

Positions: Col2, Col7, Col9 are blank.

Col2: cannot be 2,3,9 → so possible: 1,4,5,6,7,8 — but Row5 already has 4,1,7,3,5 → so missing in row: 2,6,8,9

So for Row5-Col2: possible numbers from row missing: 2,6,8,9 — but Col2 has 2,3,9 → so 2 and 9 are blocked → left with 6,8

Also, Box 4 (middle-left 3x3: rows 4-6, cols 1-3)

Box 4 contains:

Row4: _,9,_
Row5: 4,_,_
Row6: 5,_,_

Known: 9,4,5 → missing: 1,2,3,6,7,8

Row5-Col2 is in Box4 → so must be from missing in box: 1,2,3,6,7,8 — but from row, only 6,8 possible → so Row5-Col2 is either 6 or 8.

Not helpful yet.

Let’s try Row9: `4 _ _ | _ 9 7 | _ _ 2`

Missing: 1,3,5,6,8

Col2: as above, has 9,3,2 → so Row9-Col2 cannot be 3 → possible: 1,5,6,8

Col3: let's see what's in Col3:

R1: ?
R2: 2
R3: ?
R4: ?
R5: ?
R6: ?
R7: 7
R8: 5
R9: ?

Known: 2,7,5 → missing: 1,3,4,6,8,9

Row9-Col3: from row missing: 1,3,5,6,8 — but 5 is in Col3 (R8), so cannot be 5 → possible: 1,3,6,8

Still many options.

Try looking for a cell with only one possibility.

Look at Row7: `_ 3 7 | _ 4 1 | _ _ _`

Missing: 2,5,6,8,9

Col1: what's in Col1?

R1: 3
R2: ?
R3: ?
R4: ?
R5: 4
R6: 5
R7: ?
R8: ?
R9: 4 ← wait, R9-Col1 is 4, R5-Col1 is 4? That can't be!

Mistake again.

Grid:

Row5: 4 _ | ... → so R5-Col1 = 4
Row9: 4 _ _ | ... → R9-Col1 = 4 → same column! Two 4s in Col1? Impossible.

I think I misread the grid layout.

Let me write the grid clearly with positions.

The grid is 9x9. Let's index rows 1-9, columns 1-9.

Given:

Row 1: Col1=3, Col4=6, Col5=1, Col9=8 → others blank
Row 2: Col3=2, Col5=3, Col7=7, Col8=6 → others blank
Row 3: Col4=7, Col5=5, Col7=2, Col8=9 → others blank
Row 4: Col2=9, Col4=8, Col8=1 → others blank
Row 5: Col1=4, Col4=1, Col5=7, Col6=3, Col8=5 → others blank
Row 6: Col1=5, Col5=9, Col8=2 → others blank
Row 7: Col2=3, Col3=7, Col5=4, Col6=1 → others blank
Row 8: Col2=2, Col3=5, Col5=8, Col7=9 → others blank
Row 9: Col1=4, Col5=9, Col6=7, Col9=2 → others blank

Now, check for duplicates in columns.

Col1: R1=3, R5=4, R6=5, R9=4 → R5 and R9 both have 4 in Col1? That's invalid.

But in the original image description, Row9 starts with "4", and Row5 starts with "4" — but they are in the same column? That would be a mistake.

Perhaps I have the rows wrong.

Let me read the user's input again:

"3 | 6 1 | 8
2 | 3 | 7 6
| 7 5 | 2 9
9 | 8 | 1
4 | 1 7 3 | 5
5 | 9 | 2
3 7 | 4 1 |
2 5 | 8 | 9
4 | 9 7 | 2 "

This is formatted with spaces. Let's parse it properly.

It seems like each line is a row, and within each row, there are groups separated by |.

So Row 1: "3 | 6 1 | 8" → so Col1=3, then two blanks, then Col4=6, Col5=1, then three blanks, then Col9=8? But that would be 9 columns.

Typically, Sudoku is shown as 3 groups of 3.

So for Row 1: first group: "3 _ _" , second group: "6 1 _" , third group: "_ _ 8" → so Col1=3, Col2=?, Col3=?, Col4=6, Col5=1, Col6=?, Col7=?, Col8=?, Col9=8

Similarly, Row 2: " 2 | 3 | 7 6 " → first group: "_ _ 2", second: "_ 3 _", third: "7 6 _" → so Col3=2, Col5=3, Col7=7, Col8=6

Row 3: " | 7 5 | 2 9 " → first group: "_ _ _", second: "7 5 _", third: "2 9 _" → Col4=7, Col5=5, Col7=2, Col8=9

Row 4: " 9 | 8 | 1 " → first: "_ 9 _", second: "8 _ _", third: "_ 1 _" → Col2=9, Col4=8, Col8=1

Row 5: "4 | 1 7 3 | 5 " → first: "4 _ _", second: "1 7 3", third: "_ 5 _" → Col1=4, Col4=1, Col5=7, Col6=3, Col8=5

Row 6: "5 | 9 | 2 " → first: "5 _ _", second: "_ 9 _", third: "_ 2 _" → Col1=5, Col5=9, Col8=2

Row 7: " 3 7 | 4 1 | " → first: "_ 3 7", second: "_ 4 1", third: "_ _ _" → Col2=3, Col3=7, Col5=4, Col6=1

Row 8: " 2 5 | 8 | 9 " → first: "_ 2 5", second: "_ 8 _", third: "9 _ _" → Col2=2, Col3=5, Col5=8, Col7=9

Row 9: "4 | 9 7 | 2 " → first: "4 _ _", second: "_ 9 7", third: "_ _ 2" → Col1=4, Col5=9, Col6=7, Col9=2

Now, check Col1: R1=3, R5=4, R6=5, R9=4 → R5 and R9 both have 4 in Col1? That's a conflict.

But in Row5, it's "4 | ..." which is Col1=4, and Row9 "4 | ..." Col1=4 — same column, same number — impossible for Sudoku.

Unless... perhaps the formatting is off.

Maybe in Row9, "4 | 9 7 | 2 " means Col1=4, then two blanks, then Col4=?, Col5=9, Col6=7, then three blanks, then Col9=2 — but still Col1=4 for both R5 and R9.

Perhaps it's a typo in the problem, or I need to assume it's correct and proceed.

Another possibility: in some representations, the first character might not be Col1 if there are leading spaces, but in this case, for Row1, "3" is likely Col1.

Let's count the characters.

For Row1: "3 | 6 1 | 8" — let's split by |.

Part1: "3 " — 4 characters, but probably "3" followed by two spaces, so three positions: '3', ' ', ' ' — so Col1=3, Col2=blank, Col3=blank

Part2: " 6 1 " — ' ', '6', ' ', '1', ' ' — but that's 5 characters, should be 3 for the group.

This is ambiguous.

Perhaps it's better to assume that each "group" has exactly 3 cells, and the spaces are separators.

Standard way: when written as "A B C | D E F | G H I", it means Col1=A, Col2=B, Col3=C, Col4=D, etc.

In the user's input, for Row1: "3 | 6 1 | 8" — this might mean:

- First group: "3 _ _" (since "3 " could be 3 and two blanks)
- Second group: "6 1 _" ( "6 1 " might be 6,1, and blank)
- Third group: "_ _ 8" ( " 8" might be two blanks and 8)

Similarly, Row2: " 2 | 3 | 7 6 " — first group: "_ _ 2", second: "_ 3 _", third: "7 6 _"

To avoid confusion, let's list all given numbers with their positions based on common interpretation.

Assume that each row is divided into three parts by |, and each part has three cells, with spaces indicating blanks.

So for Row 1: "3 | 6 1 | 8"
- Part1: "3 _ _" → Col1=3, Col2= , Col3=
- Part2: "6 1 _" → Col4=6, Col5=1, Col6=
- Part3: "_ _ 8" → Col7= , Col8= , Col9=8

Row 2: " 2 | 3 | 7 6 "
- Part1: "_ _ 2" → Col1= , Col2= , Col3=2
- Part2: "_ 3 _" → Col4= , Col5=3, Col6=
- Part3: "7 6 _" → Col7=7, Col8=6, Col9=

Row 3: " | 7 5 | 2 9 "
- Part1: "_ _ _" → all blank
- Part2: "7 5 _" → Col4=7, Col5=5, Col6=
- Part3: "2 9 _" → Col7=2, Col8=9, Col9=

Row 4: " 9 | 8 | 1 "
- Part1: "_ 9 _" → Col1= , Col2=9, Col3=
- Part2: "8 _ _" → Col4=8, Col5= , Col6=
- Part3: "_ 1 _" → Col7= , Col8=1, Col9=

Row 5: "4 | 1 7 3 | 5 "
- Part1: "4 _ _" → Col1=4, Col2= , Col3=
- Part2: "1 7 3" → Col4=1, Col5=7, Col6=3
- Part3: "_ 5 _" → Col7= , Col8=5, Col9=

Row 6: "5 | 9 | 2 "
- Part1: "5 _ _" → Col1=5, Col2= , Col3=
- Part2: "_ 9 _" → Col4= , Col5=9, Col6=
- Part3: "_ 2 _" → Col7= , Col8=2, Col9=

Row 7: " 3 7 | 4 1 | "
- Part1: "_ 3 7" → Col1= , Col2=3, Col3=7
- Part2: "_ 4 1" → Col4= , Col5=4, Col6=1
- Part3: "_ _ _" → all blank

Row 8: " 2 5 | 8 | 9 "
- Part1: "_ 2 5" → Col1= , Col2=2, Col3=5
- Part2: "_ 8 _" → Col4= , Col5=8, Col6=
- Part3: "9 _ _" → Col7=9, Col8= , Col9=

Row 9: "4 | 9 7 | 2 "
- Part1: "4 _ _" → Col1=4, Col2= , Col3=
- Part2: "_ 9 7" → Col4= , Col5=9, Col6=7
- Part3: "_ _ 2" → Col7= , Col8= , Col9=2

Now, check Col1:
R1: 3
R2:
R3:
R4:
R5: 4
R6: 5
R7:
R8:
R9: 4 → oh, R5 and R9 both have 4 in Col1. This is invalid for Sudoku.

Unless... in Row9, "4 |" might mean Col1 is not 4, but perhaps the "4" is for a different column.

Perhaps the formatting has extra spaces, and "4 |" for Row9 means that the first cell is blank, and "4" is later, but that doesn't make sense.

Another idea: in some text representations, the number is placed where it belongs, and spaces are just padding.

For example, in Row1: "3 | 6 1 | 8" — the "3" is at position 1, "6" at position 4, "1" at position 5, "8" at position 9.

Similarly, for Row9: "4 | 9 7 | 2 " — "4" at position 1, "9" at position 5, "7" at position 6, "2" at position 9.

So Col1 has R1=3, R5=4, R6=5, R9=4 — indeed two 4s.

This must be a mistake in the problem or in my reading.

Perhaps for Row5, "4 |" means Col1=4, but for Row9, "4 |" might be a typo, and it should be something else.

Or perhaps in Row9, the "4" is for Col1, but in standard Sudoku, it's allowed to have the same number in different rows, but not same column — here same column, so error.

Unless the grid is not aligned, but that doesn't make sense.

Let's look back at the user's message: "4 | 9 7 | 2 " for Row9, and for Row5: "4 | 1 7 3 | 5 " — both start with "4 |", so likely both have 4 in Col1.

But that can't be. Perhaps it's a different puzzle, or I need to proceed assuming it's correct and see.

Maybe "4 |" for Row9 means that the first cell is 4, but in the context, perhaps it's Col1, and we have to live with it, but that would make the puzzle unsolvable.

Another possibility: in Row5, "4 |" might mean Col1=4, but in Row9, "4 |" might be misaligned, and the 4 is for a different column.

Let's count the characters in the string.

For Row5: "4 | 1 7 3 | 5 " — let's remove spaces or consider positions.

Perhaps it's better to assume that the numbers are given, and blanks are to be filled, and the duplicate is a red herring or error, but for the sake of solving, let's assume that in Row9, the "4" is not in Col1, but that doesn't match the format.

Let's try to ignore the conflict and solve as much as possible.

Perhaps in Col1, R5 and R9 both have 4, but that's impossible, so maybe for Row9, the "4" is for Col1, but in the actual puzzle, it's different, or perhaps it's a test.

I recall that in some online puzzles, there might be errors, but for this, let's try to solve it by filling in what we can.

Let's start with Row 7: "_ 3 7 | _ 4 1 | _ _ _"

So Col2=3, Col3=7, Col5=4, Col6=1

Missing in row: 2,5,6,8,9

Now, look at Col1 for Row7: what can go there.

Col1 has: R1=3, R5=4, R6=5, R9=4 — but R9=4 is duplicate, so perhaps R9-Col1 is not 4, or we have to accept it.

Assume that R9-Col1 is 4, and R5-Col1 is 4, but that's invalid, so perhaps in the grid, for Row5, "4 |" means something else.

Let's look at the very first line: "3 | 6 1 | 8" — perhaps the "3" is Col1, and for Row5, "4 |" is Col1=4, but for Row9, "4 |" might be a mistake, and it should be " _ _ _ " or something.

Perhaps "4 |" for Row9 means that the first cell is blank, and "4" is not there, but the text says "4 |", so likely it's 4.

Another idea: in some formats, the number is written without space, but here it's with spaces.

Let's calculate the position.

Suppose each cell is represented by a character, and | are separators.

For Row1: "3 | 6 1 | 8" — let's say the string is "3 | 6 1 | 8"

If we split by '|', we get ["3 ", " 6 1 ", " 8"]

Then for each part, trim and split by space, but it's messy.

Perhaps it's intended that:

- For Row1: Col1=3, Col4=6, Col5=1, Col9=8
- For Row2: Col3=2, Col5=3, Col7=7, Col8=6
- For Row3: Col4=7, Col5=5, Col7=2, Col8=9
- For Row4: Col2=9, Col4=8, Col8=1
- For Row5: Col1=4, Col4=1, Col5=7, Col6=3, Col8=5
- For Row6: Col1=5, Col5=9, Col8=2
- For Row7: Col2=3, Col3=7, Col5=4, Col6=1
- For Row8: Col2=2, Col3=5, Col5=8, Col7=9
- For Row9: Col1=4, Col5=9, Col6=7, Col9=2

And accept that Col1 has two 4s, but that can't be, so perhaps for Row9, Col1 is not 4, but the "4" is for a different purpose.

Notice that in Row9, it's "4 | 9 7 | 2 ", and in Row5, "4 | 1 7 3 | 5 ", so both have "4 |" at the beginning, but in Row5, after | is "1 7 3", which is Col4,5,6, so for Row9, after | is " 9 7", which might be Col4,5,6, so Col4= , Col5=9, Col6=7, so the "4" before | is Col1.

Same for Row5.

So to resolve this, perhaps the puzzle has a typo, and for Row9, it should be " _ _ _ | 9 7 | 2 " or something, but as given, we have to work with it.

Maybe "4 |" for Row9 means that Col1 is 4, but in the context of the whole grid, it's ok if we consider that R5 and R9 are different, but same column, so not ok.

Unless the grid is 9x9, and Col1 can have only one 4, so this is an error.

Perhaps for Row5, "4 |" means Col1=4, but for Row9, "4 |" might be " _ 4 _ " or something, but the text shows "4 |", so likely Col1=4.

I think there might be a mistake in the problem statement, but for the sake of completing the task, let's assume that in Row9, the "4" is not in Col1, but that doesn't make sense.

Another possibility: in some representations, the first number might be for Col1, but in Row9, "4 |" could mean that the first cell is 4, but perhaps it's a different indexing.

Let's try to solve it by ignoring the conflict and see if we can fill other cells.

Let's look at Box 7 (bottom-left 3x3: rows 7-9, cols 1-3)

Box 7 contains:

Row7: Col1=?, Col2=3, Col3=7
Row8: Col1=?, Col2=2, Col3=5
Row9: Col1=4, Col2=?, Col3=?

So known: 3,7,2,5,4 → missing: 1,6,8,9

Col1 for Box7: R7-Col1, R8-Col1, R9-Col1=4

So R7-Col1 and R8-Col1 must be from 1,6,8,9, but since Col1 has R1=3, R5=4, R6=5, R9=4, so for R7-Col1, cannot be 3,4,5 — so can be 1,2,6,7,8,9 — but in box, missing 1,6,8,9, and 2,7 are already in box (Col2=3, but 2 is in R8-Col2, 7 in R7-Col3), so for R7-Col1, possible from box missing: 1,6,8,9

Similarly for R8-Col1.

But also, Col1 has R1=3, R5=4, R6=5, R9=4 — so values in Col1: 3,4,5,4 — so unique values: 3,4,5 — so missing in Col1: 1,2,6,7,8,9

So for R7-Col1, can be 1,2,6,7,8,9, but in box, 2 and 7 are already present (R8-Col2=2, R7-Col3=7), so cannot be 2 or 7, so possible: 1,6,8,9

Same as before.

Now, let's look at Row7: "_ 3 7 | _ 4 1 | _ _ _"

So Col1, Col4, Col7, Col8, Col9 are blank.

Missing in row: 2,5,6,8,9

Col4: what's in Col4?

R1: 6
R2: ?
R3: 7
R4: 8
R5: 1
R6: ?
R7: ?
R8: ?
R9: ?

Known: 6,7,8,1 → missing: 2,3,4,5,9

For Row7-Col4, from row missing: 2,5,6,8,9 — but 6,8 are in Col4 (R1=6, R4=8), so cannot be 6 or 8 — so possible: 2,5,9

Also, Box 8 (bottom-middle: rows 7-9, cols 4-6)

Box 8 contains:

Row7: Col4=?, Col5=4, Col6=1
Row8: Col4=?, Col5=8, Col6=?
Row9: Col4=?, Col5=9, Col6=7

So known: 4,1,8,9,7 → missing: 2,3,5,6

For Row7-Col4, must be from box missing: 2,3,5,6 — but from row, possible 2,5,9 — intersection: 2,5

So Row7-Col4 is 2 or 5.

Similarly, Col4 has missing 2,3,4,5,9, but 4 is in R7-Col5, not in Col4, so for Col4, missing 2,3,4,5,9, but 4 is not in Col4 yet, so ok.

But for Row7-Col4, possible 2 or 5.

Now, let's look at Row8: "_ 2 5 | _ 8 _ | 9 _ _"

So Col1, Col4, Col6, Col8, Col9 blank.

Missing in row: 1,3,4,6,7

Col4 for Row8: from above, Col4 missing 2,3,4,5,9 — so for Row8-Col4, possible from row missing: 1,3,4,6,7 — intersection with Col4 missing: 3,4

Also, Box 8 missing: 2,3,5,6 — so for Row8-Col4, must be from 2,3,5,6 — intersection with above: 3

So Row8-Col4 = 3

Great! So we can fill that.

So Row8, Col4 = 3

Update the grid.

Now, Col4 has: R1=6, R3=7, R4=8, R5=1, R8=3, and R2, R6, R7, R9 blank.

Missing in Col4: 2,4,5,9

For Row7-Col4, we had possible 2 or 5, and now Col4 has 3 added, so still 2,4,5,9 missing, so 2 or 5 still possible.

But in Box 8, with R8-Col4=3, now Box 8 has: R7-Col5=4, R7-Col6=1, R8-Col5=8, R8-Col4=3, R9-Col5=9, R9-Col6=7 — so known: 4,1,8,3,9,7 — missing: 2,5,6

For Row7-Col4, must be from 2,5,6 — and from row, possible 2,5,9 — so intersection 2,5

Same as before.

Now, let's look at Row9: "4 _ _ | _ 9 7 | _ _ 2" so Col1=4, Col5=9, Col6=7, Col9=2

Missing in row: 1,3,5,6,8

Col4 for Row9: from Col4 missing: 2,4,5,9 — but 4 and 9 are in the row or column? Col4 has R1=6, R3=7, R4=8, R5=1, R8=3, so missing 2,4,5,9

For Row9-Col4, from row missing: 1,3,5,6,8 — intersection with Col4 missing: 5 (since 2,4,9 not in row missing, 5 is in both)

Row missing: 1,3,5,6,8
Col4 missing: 2,4,5,9
Intersection: 5

Also, Box 8 missing: 2,5,6 — so 5 is in both.

So Row9-Col4 = 5

Fill that in.

So Row9, Col4 = 5

Now, Col4 has: R1=6, R3=7, R4=8, R5=1, R8=3, R9=5 — so missing: 2,4,9

For Row7-Col4, possible 2 or 5, but 5 is now in Col4 (R9), so cannot be 5 — so must be 2

So Row7-Col4 = 2

Fill that in.

Now, Row7: Col4=2, and we have Col2=3, Col3=7, Col5=4, Col6=1, so far: _ 3 7 | 2 4 1 | _ _ _

Missing in row: 5,6,8,9 (since 2 is filled)

Previously missing 2,5,6,8,9, now 2 is filled, so missing 5,6,8,9

Col1 for Row7: as before, possible 1,6,8,9 (from box and column)

But row missing 5,6,8,9, so for Col1, possible 6,8,9 (since 1 not in row missing)

Box 7 missing: earlier we had 1,6,8,9, but now with R7-Col4=2, but Col4 is not in Box 7, Box 7 is cols 1-3, so still missing 1,6,8,9 for Box 7.

For R7-Col1, must be from box missing: 1,6,8,9, and from row missing: 5,6,8,9, so intersection: 6,8,9

Also, Col1 has R1=3, R5=4, R6=5, R9=4 — so values 3,4,5,4 — so unique 3,4,5 — missing 1,2,6,7,8,9

So for R7-Col1, can be 6,8,9 (since 1,2,7 not in row missing or box constraint)

2 is in row? Row7 has Col4=2, so 2 is used, so not available.

So possible 6,8,9 for R7-Col1.

Now, let's look at Row6: "5 _ _ | _ 9 _ | _ 2 _" so Col1=5, Col5=9, Col8=2

Missing: 1,3,4,6,7,8

Col4 for Row6: Col4 missing 2,4,9 — but 2 and 9 are in the row or column? Col4 has R1=6, R3=7, R4=8, R5=1, R8=3, R9=5, so missing 2,4,9

For Row6-Col4, from row missing: 1,3,4,6,7,8 — intersection with Col4 missing: 4 (since 2,9 not in row missing)

Also, Box 5 (center: rows 4-6, cols 4-6)

Box 5 contains:

Row4: Col4=8, Col5=?, Col6=?
Row5: Col4=1, Col5=7, Col6=3
Row6: Col4=?, Col5=9, Col6=?

So known: 8,1,7,3,9 — missing: 2,4,5,6

For Row6-Col4, must be from 2,4,5,6 — and from above, only 4 is in intersection with row and col, so Row6-Col4 = 4

Fill that in.

So Row6, Col4 = 4

Now, Col4 has: R1=6, R3=7, R4=8, R5=1, R6=4, R8=3, R9=5 — so missing: 2,9

For Row2-Col4 and Row7-Col4 is already filled as 2, so only Row2-Col4 left for Col4.

Col4 missing 2,9, and R7-Col4=2, so only 9 left for R2-Col4.

So Row2-Col4 = 9

Fill that in.

Now, let's update what we have.

Current grid:

Row1: 3 _ _ | 6 1 _ | _ _ 8
Row2: _ _ 2 | 9 3 _ | 7 6 _
Row3: _ _ _ | 7 5 _ | 2 9 _
Row4: _ 9 _ | 8 _ _ | _ 1 _
Row5: 4 _ _ | 1 7 3 | _ 5 _
Row6: 5 _ _ | 4 9 _ | _ 2 _
Row7: _ 3 7 | 2 4 1 | _ _ _
Row8: _ 2 5 | 3 8 _ | 9 _ _
Row9: 4 _ _ | 5 9 7 | _ _ 2

Now, let's continue.

Look at Row2: "_ _ 2 | 9 3 _ | 7 6 _"

So Col1,2,6,9 blank.

Missing in row: 1,4,5,8

Col6: what's in Col6?

R1: ?
R2: ?
R3: ?
R4: ?
R5: 3
R6: ?
R7: 1
R8: ?
R9: 7

Known: 3,1,7 → missing: 2,4,5,6,8,9

For Row2-Col6, from row missing: 1,4,5,8 — intersection with Col6 missing: 4,5,8 (1 is in Col6 R7, so not available)

Also, Box 2 (top-middle: rows 1-3, cols 4-6)

Box 2 contains:

Row1: Col4=6, Col5=1, Col6=?
Row2: Col4=9, Col5=3, Col6=?
Row3: Col4=7, Col5=5, Col6=?

So known: 6,1,9,3,7,5 — missing: 2,4,8

For Row2-Col6, must be from 2,4,8 — and from row missing: 1,4,5,8 — intersection: 4,8

So possible 4 or 8.

Now, Col6 has R5=3, R7=1, R9=7, so for Row2-Col6, can be 4 or 8.

Let's look at Row3: "_ _ _ | 7 5 _ | 2 9 _"

So Col1,2,3,6,9 blank.

Missing in row: 1,3,4,6,8

Col6 for Row3: from Col6 missing: 2,4,5,6,8,9 — intersection with row missing: 4,6,8

Box 2 missing: 2,4,8 — so for Row3-Col6, must be from 2,4,8 — intersection with above: 4,8

So possible 4 or 8.

Now, in Box 2, missing 2,4,8, and we have three cells: R1-Col6, R2-Col6, R3-Col6

Each must be 2,4,8 in some order.

For R1-Col6: Row1: "3 _ _ | 6 1 _ | _ _ 8" so missing in row: 2,4,5,7,9

Col6 missing: 2,4,5,6,8,9 — intersection: 2,4,5,9

Box 2 missing: 2,4,8 — so for R1-Col6, must be from 2,4,8 — intersection with above: 2,4

So R1-Col6 is 2 or 4.

Similarly, R2-Col6 is 4 or 8, R3-Col6 is 4 or 8.

But in Box 2, only one 4, so if R1-Col6 is 2 or 4, and R2 and R3 are 4 or 8, then if R1-Col6 is 4, then R2 and R3 must be 2 and 8, but R2 and R3 can only be 4 or 8, not 2, so contradiction if R1-Col6=4.

Let's see:

If R1-Col6 = 4, then for Box 2, remaining missing 2,8 for R2-Col6 and R3-Col6.

But R2-Col6 can be 4 or 8, but 4 is taken, so must be 8.

R3-Col6 can be 4 or 8, but 4 taken, 8 taken by R2, so must be 2, but R3-Col6 can only be 4 or 8 from earlier constraint? No, from above, for R3-Col6, we said must be from 2,4,8 for box, and from row and col, 4,6,8, but 6 not in box missing, so only 4,8, but if 4 and 8 are taken, then 2 is possible, but is 2 allowed for R3-Col6?

From row missing for Row3: 1,3,4,6,8 — 2 is not in missing, because Row3 has Col7=2, so 2 is already in the row, so cannot be in Col6.

Row3: Col7=2, so 2 is used, so for Col6, cannot be 2.

So for R3-Col6, cannot be 2, must be 4 or 8.

Similarly, for R2-Col6, cannot be 2, because if it were 2, but from row missing, 2 is not in missing for Row2? Row2 has Col3=2, so 2 is used, so cannot be in Col6.

Row2: Col3=2, so 2 is in the row, so for Col6, cannot be 2.

So for both R2-Col6 and R3-Col6, cannot be 2, must be 4 or 8.

For R1-Col6, can be 2 or 4.

In Box 2, missing 2,4,8.

If R1-Col6 = 2, then R2-Col6 and R3-Col6 must be 4 and 8.

If R1-Col6 = 4, then R2-Col6 and R3-Col6 must be 2 and 8, but neither can be 2, so impossible.

Therefore, R1-Col6 must be 2.

Then R2-Col6 and R3-Col6 are 4 and 8 in some order.

So fill R1-Col6 = 2

Now, Row1: 3 _ _ | 6 1 2 | _ _ 8

Missing in row: 4,5,7,9

Col6 is filled.

Now, for R2-Col6 and R3-Col6: 4 and 8.

Look at Col6: currently R1=2, R5=3, R7=1, R9=7, and R2, R3, R4, R6, R8 blank.

Missing in Col6: 4,5,6,8,9

For R2-Col6: possible 4 or 8

For R3-Col6: possible 4 or 8

Also, Row2 missing: 1,4,5,8 (since Col3=2, Col4=9, Col5=3, Col7=7, Col8=6, so used: 2,9,3,7,6 — missing: 1,4,5,8)

Similarly, Row3 missing: 1,3,4,6,8 (used: 7,5,2,9 — so missing 1,3,4,6,8)

Now, let's look at Box 2: with R1-Col6=2, so missing 4,8 for R2-Col6 and R3-Col6.

Now, perhaps we can use other constraints.

Look at Row4: "_ 9 _ | 8 _ _ | _ 1 _"

So Col1,3,5,6,7,9 blank.

Missing in row: 2,3,4,5,6,7

Col6 for Row4: from Col6 missing: 4,5,6,8,9 — intersection with row missing: 4,5,6

Box 5 (rows 4-6, cols 4-6): known: R4-Col4=8, R5-Col4=1, R5-Col5=7, R5-Col6=3, R6-Col4=4, R6-Col5=9, so known: 8,1,7,3,4,9 — missing: 2,5,6

For Row4-Col6, must be from 2,5,6 — and from above, 4,5,6, so intersection: 5,6

So possible 5 or 6.

Similarly, for Row6-Col6: Row6: "5 _ _ | 4 9 _ | _ 2 _" so Col6 blank.

Row6 missing: 1,3,6,7,8 (used: 5,4,9,2 — so missing 1,3,6,7,8)

Col6 missing: 4,5,6,8,9 — intersection: 6,8

Box 5 missing: 2,5,6 — so for Row6-Col6, must be from 2,5,6 — intersection with above: 6

So Row6-Col6 = 6

Fill that in.

So Row6, Col6 = 6

Now, Col6 has R1=2, R5=3, R6=6, R7=1, R9=7 — so missing: 4,5,8,9

For Row4-Col6, possible 5 or 6, but 6 is now in Col6, so must be 5

So Row4-Col6 = 5

Fill that in.

Now, Col6 has R4=5, so missing: 4,8,9

For R2-Col6 and R3-Col6, must be 4 and 8.

Now, Row2 missing: 1,4,5,8 — but 5 is in Col6? Not yet, but for R2-Col6, can be 4 or 8.

Similarly for R3.

Now, look at Row3: missing 1,3,4,6,8

If R3-Col6 = 4 or 8.

Also, in Box 2, R2-Col6 and R3-Col6 are 4 and 8.

Now, let's look at Col5 for help, but Col5 is almost full.

Col5: R1=1, R2=3, R3=5, R4=?, R5=7, R6=9, R7=4, R8=8, R9=9 — R6=9, R9=9? Conflict!

R6-Col5=9, R9-Col5=9 — same column, two 9s.

Oh no! Another conflict.

In the grid, Row6: "5 | 9 | 2 " so Col5=9

Row9: "4 | 9 7 | 2 " so Col5=9

So Col5 has two 9s: R6 and R9.

This is invalid.

So the puzzle as given has errors: Col1 has two 4s (R5 and R9), Col5 has two 9s (R6 and R9).

Probably a typo in the problem.

Perhaps for Row9, the "9" is not in Col5, but in the text, " | 9 7 | " suggests Col5=9, Col6=7.

Similarly for Row6, " | 9 | " suggests Col5=9.

So likely, the puzzle has mistakes.

For the sake of completing the task, perhaps we can assume that in Row9, Col5 is not 9, but that doesn't match.

Or perhaps " | 9 7 | " for Row9 means Col4= , Col5=9, Col6=7, but maybe it's Col4=9, Col5=7, but the text has "9 7" with space, so likely Col5=9, Col6=7.

I think there might be a mistake in the user's input, but since this is a homework helper, perhaps I should provide the solved grid as per standard, or note the error.

But the instruction is to solve the problem accurately, so perhaps I need to correct it.

Maybe in Row9, "4 | 9 7 | 2 " means that the first "4" is Col1, then two blanks, then "9" is Col4, "7" is Col5, but that would be unusual, because usually the groups are together.

In some formats, the | separate the boxes, so for Row9: "4 | 9 7 | 2 " might mean:

- First box: "4 _ _" → Col1=4, Col2= , Col3=
- Second box: " 9 7" → but " 9 7" might be Col4= , Col5=9, Col6=7 or Col4=9, Col5=7, Col6=

The text has " | 9 7 | " which likely means after |, there is space, then 9, space, 7, so probably Col4= , Col5=9, Col6=7.

Similarly for others.

To resolve, perhaps for Row6, " | 9 | " means Col5=9, but for Row9, " | 9 7 | " might be intended as Col4=9, Col5=7, but the "9 7" suggests two numbers.

I think the best way is to assume that the puzzle is correct as per common Sudoku, and the duplicates are errors, but for this response, I'll provide a solved version by assuming that in Row9, Col5 is not 9, but let's say it's different.

Perhaps "9 7" for Row9 second box means Col5=9, Col6=7, but in Row6, "9" is for Col5, so conflict.

Another idea: in Row6, " | 9 | " might mean that the 9 is for Col5, but in the context, perhaps it's Col6, but the text has " | 9 | " which is likely Col5.

I recall that in the initial grid, for Row6: "5 | 9 | 2 " and for Row9: "4 | 9 7 | 2 ", so perhaps for Row9, the "9" is for Col4, and "7" for Col5, but that would be inconsistent with the spacing.

Let's look at Row5: "4 | 1 7 3 | 5 " — here "1 7 3" is clearly Col4,5,6.

For Row9: " | 9 7 | " — if it were "9 7" without space, but it's " 9 7" with spaces, so likely Col4= , Col5=9, Col6=7.

Similarly, for Row6: " | 9 | " — " 9 " might mean Col4= , Col5=9, Col6=

So to fix the conflict, perhaps in Row9, Col5 is not 9, but the puzzle intends it to be, or vice versa.

Perhaps for Row6, the "9" is for Col6, but the text has " | 9 | " which suggests it's in the middle of the group.

I think for the purpose of this exercise, I'll assume that the puzzle is solvable, and the duplicates are typos, and proceed with the solving as far as possible, or provide a standard solution.

Perhaps the "4" in Row9 Col1 is a mistake, and it should be something else.

Let's assume that in Row9, Col1 is not 4, but blank, and the "4" is for a different cell, but that doesn't match.

Another thought: in the user's message, for Row9: "4 | 9 7 | 2 " and for Row5: "4 | 1 7 3 | 5 ", but perhaps in Row9, the "4" is for Col1, but in the actual puzzle, it's correct if we consider that R5 and R9 are different, but same column, so not.

I think I need to box the answer as per the solving, but since there are conflicts, perhaps the final answer is the completed grid with the conflicts resolved by choosing one.

Perhaps for Col1, R9 is not 4, but let's say it's 1 or something.

To move forward, let's assume that in Row9, Col1 is 1, for example, but that's arbitrary.

Perhaps the "4" in "4 |" for Row9 is a typo, and it should be " _ _ _ " or "1 _ _ ".

But for the sake of completing, I'll provide the solved grid as per standard Sudoku solving, ignoring the conflicts for now.

From earlier, we have:

After filling:

R1-Col6 = 2
R6-Col6 = 6
R4-Col6 = 5
R8-Col4 = 3
R9-Col4 = 5
R7-Col4 = 2
R2-Col4 = 9
R6-Col4 = 4

And Col4 is complete: R1=6, R2=9, R3=7, R4=8, R5=1, R6=4, R7=2, R8=3, R9=5

Col6: R1=2, R4=5, R5=3, R6=6, R7=1, R9=7, so missing R2, R3, R8

With R2-Col6 and R3-Col6 being 4 and 8, and R8-Col6 blank.

Col6 missing: 4,8,9 (since 2,5,3,6,1,7 are present)

R8-Col6: Row8: "_ 2 5 | 3 8 _ | 9 _ _" so Col6 blank.

Row8 missing: 1,4,6,7 (used: 2,5,3,8,9 — so missing 1,4,6,7)

Col6 missing: 4,8,9 — intersection: 4

Also, Box 8: rows 7-9, cols 4-6: R7-Col4=2, R7-Col5=4, R7-Col6=1, R8-Col4=3, R8-Col5=8, R8-Col6=?, R9-Col4=5, R9-Col5=9, R9-Col6=7

So known: 2,4,1,3,8,5,9,7 — missing: 6

So R8-Col6 = 6

Fill that in.

So Row8, Col6 = 6

Now, Col6 has R8=6, so missing: 4,8,9 minus 6, so still 4,8,9, but R8=6, so for R2 and R3, must be 4 and 8, and 9 is left for another, but Col6 has 9 cells, all should be filled.

Col6: R1=2, R2=?, R3=?, R4=5, R5=3, R6=6, R7=1, R8=6? R6=6, R8=6 — conflict! R6-Col6=6, R8-Col6=6 — same column, two 6s.

Oh no! Another conflict.

R6-Col6=6, and we just set R8-Col6=6, but in Box 8, we said missing 6, but R6-Col6 is in Box 5, not Box 8.

Box 8 is rows 7-9, cols 4-6, so R6 is not in Box 8.

In Box 8, with R7-Col4=2, R7-Col5=4, R7-Col6=1, R8-Col4=3, R8-Col5=8, R8-Col6=?, R9-Col4=5, R9-Col5=9, R9-Col6=7

So numbers: 2,4,1,3,8,5,9,7 — that's 8 numbers, missing 6, so R8-Col6=6.

But in Col6, R6-Col6=6, and R8-Col6=6, so same column, two 6s — invalid.

So the puzzle has multiple errors.

Given the time, and since this is a homework helper, perhaps I should provide the intended solution or note the error.

Perhaps in the original image, the numbers are different, but based on the text, it's flawed.

For the sake of providing an answer, I'll assume that in Row6, the "9" is for Col6, not Col5, but the text has " | 9 | " which is likely Col5.

Let's swap: assume that for Row6, " | 9 | " means Col6=9, and Col5 is blank, but that doesn't match the format.

Perhaps " | 9 | " means that the 9 is in the second position of the group, so for the second group, Col4,5,6, " | 9 | " might mean Col5=9, as before.

I think I need to conclude.

Perhaps the final answer is the completed grid, and for the conflicts, we can choose.

But to follow the instruction, I'll provide the solved grid as per standard, and for the duplicates, omit one.

Since the user may have meant a different puzzle, I'll box the answer as the filled grid with the values we have.

From earlier successful fills:

- R1-Col6 = 2
- R2-Col4 = 9
- R4-Col6 = 5
- R6-Col4 = 4
- R6-Col6 = 6
- R7-Col4 = 2
- R8-Col4 = 3
- R8-Col6 = 6 -- but conflict with R6-Col6=6, so perhaps R6-Col6 is not 6.

In Box 5, when we had R6-Col6, we said must be 6, but let's revisit.

Box 5: rows 4-6, cols 4-6

R4-Col4=8, R4-Col5=?, R4-Col6=?
R5-Col4=1, R5-Col5=7, R5-Col6=3
R6-Col4=4, R6-Col5=9, R6-Col6=?

Known: 8,1,7,3,4,9 — so missing 2,5,6

For R6-Col6, from row6 missing: 1,3,6,7,8 (used: 5,4,9,2 — so missing 1,3,6,7,8)

Col6 missing: at that time, before filling, but after R1-Col6=2, R4-Col6=5, etc.

At the time we filled R6-Col6, Col6 had R1=2, R5=3, R7=1, R9=7, and R4=5 (just filled), so Col6: R1=2, R4=5, R5=3, R7=1, R9=7 — so missing 4,6,8,9

For R6-Col6, from row missing: 1,3,6,7,8 — intersection with Col6 missing: 6,8

Box 5 missing: 2,5,6 — so must be from 2,5,6 — intersection with 6,8: 6

So yes, must be 6.

But then R8-Col6=6 causes conflict.

Unless in Box 8, R8-Col6 is not 6.

In Box 8, with R7-Col4=2, R7-Col5=4, R7-Col6=1, R8-Col4=3, R8-Col5=8, R8-Col6=?, R9-Col4=5, R9-Col5=9, R9-Col6=7

Numbers: 2,4,1,3,8,5,9,7 — sum or list: 1,2,3,4,5,7,8,9 — missing 6, so must be 6.

So conflict is inevitable.

Therefore, the puzzle as given has errors and cannot be solved as is.

For the purpose of this response, I'll provide a corrected version or state that.

Since the instruction is to solve accurately, and there are conflicts, perhaps the final answer is that the puzzle has errors.

But that might not be helpful.

Perhaps in Row9, the "9" is for Col4, and "7" for Col5, but then Col5 would have R6=9, R9=7, no conflict, and Col4 would have R9=9, but R2=9, so conflict in Col4.

If for Row9, " | 9 7 | " means Col4=9, Col5=7, then Col4 has R2=9, R9=9 — conflict.

If for Row6, " | 9 | " means Col6=9, then Col5 is blank for Row6, so no conflict with R9-Col5=9.

Let's try that assumption.

Assume that for Row6: "5 | 9 | 2 " means that the "9" is for Col6, not Col5.

So Col5 for Row6 is blank, Col6=9.

Similarly, for other rows, the number is in the position as per the group.

For Row6: first group "5 _ _" → Col1=5, Col2= , Col3=
Second group " 9 " → but " 9 " might mean Col4= , Col5= , Col6=9 or Col4=9, etc.