LinkedIn Mini Sudoku #166 (DiagSeries) Step-by-Step Solution – January 24, 2026

Crack today's LinkedIn Mini Sudoku #166 DiagSeries, a tricky 6x6 puzzle where each row, column, and 2x3 box needs digits 1-6 exactly once. With clues like row 1 column 4 as 3, row 2 column 1 as 1, row 2 column 5 as 4, and others, we'll solve it logically using naked singles, process of elimination, and box completions. Question ID: 166. Let's dive in!

Visualize the grid (rows 1-6 top to bottom, columns A-F left to right):

  A B C D E F
1 . . . 3 . .
2 1 . . . 4 .
3 . 2 . . . 5
4 . . 3 . . .
5 5 . . 4 . .
6 . 6 . . 5 .

Step 1: Fill Easy Naked Singles from Clues

Start with units having most clues. Look at column A: Clues at A2=1, A5=5. Row 1 (A1) can't be 1 or 5 (from col), or 3 (row clue). Box 1 possibilities narrow quickly.

• A1=2: Only spot in box 1 col A for 2 (B3=2 blocks elsewhere in row/col/box).
• F2=6: Row 2 has 1 and 4; box 2 needs 6 (F3=5 blocks 5; col F open but row forces it).

Updated grid:

  A B C D E F
1 2 . . 3 . .
2 1 . . . 4 6
3 . 2 . . . 5
4 . . 3 . . .
5 5 . . 4 . .
6 . 6 . . 5 .

Step 2: Complete Box 2 and Column F

Box 2 (rows 2-3, cols E-F) has 4 (E2), 5 (F3), 6 (F2). Missing 1,2,3.

• Row 3 col E can't be 5 (F3), 2 (B3), so E3=1 (process of elimination in row/box).
• Now box 2: E3=1, so F2=6, E2=4 leave C3? Wait, box 2 is E-F only? No—6x6 boxes are cols 1-3 (A-C), 4-6 (D-F). Correcting: Standard 2x3 boxes.

Refocus: Box top-right (rows1-3, D-F): D1=3, E2=4, F3=5, F2=6. Missing 1,2.

• D3=2? No—check row 3: B3=2 already. Actually, E3=3? Let's eliminate properly.

Step 3: Row and Column Intersections

Row 6: B6=6, F6=5. Column B: B3=2, B6=6. Box bottom-left (rows4-6,A-C) has no clues yet.

• C6=4: Col C open, but row 6 missing 1,2,3,4; box needs them, but D4=3 blocks 3, forcing via col D.
• Column D: D1=3, D4=3—wait no, two 3s invalid! Clues: D1=3? Puzzle: row1 col4=3 (D1=3), row4 col3? JSON parse accurate: row4 col3=3 (C4=3).

Accurate fills: After initial, B1=4 (row1: A1=2,D1=3; box1 can't have 1 from A2). C1=5 completes row1/box1 (1,6 left but positions force).

  A B C D E F
1 2 4 5 3 . .
2 1 . . . 4 6
3 . 2 . . . 5
4 . . 3 . . .
5 5 . . 4 . .
6 . 6 . . 5 .

Step 4: Naked Singles Cascade

• F1=1, E1=6: Row1 now full (2,4,5,3,6,1).
• Column E: E2=4, E5=4 invalid—no, E5 empty. Clues E5 null. Row5 E=4? JSON row5 col5 null, row5 col4=4 (D5=4).
• A3=4: Row3 B3=2,F3=5; col A A1=2,A2=1,A5=5; box1 needs 6,3 but positions.
• Chain: C2=3 (row2:1,_,_,_,4,6; box top-left missing).

Step 5: Box Completions and Pairs

Middle box row2-3 colD-F: Now has numbers forcing D2=5 (only spot), D3=1? Logical flow:

• Focus number **3**: Positions blocked by clues D1=3,C4=3.
• B5=1: Row5 A5=5,D5=4; col B.
• A4=6: Col A now many filled.

Progress to near-full:
Full top row confirmed.
Row2:1,3,6,5,4,?

Step 6: Final Eliminations

Bottom row6: .6. . .5. → A6=3 (only missing after eliminations), C6=1?** No—D6=2, E6=? Flow: