LinkedIn 6x6 Sudoku #213 Pro-Tips Speed-Run

LinkedIn 6x6 Sudoku #213: Speed-Run Pro-Tips

Drop into #213 with eyes on the givens: row 1 col 3 is 1, row 2 col 2 is 2, row 2 col 4 is 3, row 3 col 1 is 4, row 3 col 3 is 5, row 3 col 5 is 6, row 4 col 2 is 6, row 4 col 4 is 5, row 4 col 6 is 1, row 5 col 3 is 2, row 5 col 5 is 3, row 6 col 4 is 4. Grid looks sparse but packed with early wins. Hit the fullest rows and boxes first for quick fills.

Opening Salvo: Fullest Areas and Cross-Hatching

Scan row 3: 4 _ 5 _ 6 _. Missing 1,2,3. Cross-hatch column 2: sees 2 (row2) and 6 (row4), so only 1,3,5 open but row needs 1,2,3. Wait, 2 blocked by row2 col2. Nail row3 col2 as 1: row lacks it, column open. Boom, row3 now 4,1,5,_,6,_.

Cross-hatch row3 col4: must be 2 or 3. Column4 has 3 (row2),5 (row4), so row3 col4 is 2. Row3 seals as 4,1,5,2,6,3. Chain reaction: column6 row1-2 open for 2,5 (others hit).

Hidden Singles in Boxes: Momentum Builder

Top-right box (rows1-3, cols4-6): givens 3(row2col4),6(row3col5). Now +2(row3col4). Sees 1(r1c3 via row),4,5(r3c3). Hidden single for 4 in row1 col6: only spot left after scanning row1 (has1), col6 (has3,6 now), box elims. Row1 col5 must be 2: row1 needs 2,4,5,6; 4 just placed, col5 open.

Shift to bottom-left box (rows4-6, cols1-3): givens 6(r4c2),2(r5c3),1(r4c6 but wrong box). Cross-hatch 3's: row5 has it col5, so row5 col1 or col2. But col1 row3=4 blocks? Hidden single pops 3 in row6 col1? No, build step-by-step.

Crucial Square: Row 4 Col 1 (The Crack)

Here's the crucial square: row4 col1. After early fills (row3 done, top row partial), scan row4: _ 6 _ 5 _ 1. Has1,5,6. Needs2,3,4. Col1 sees4(r3), so2 or3. But box1 (rows4-6 cols1-3) has6(r4c2),2(r5c3). So row4 col1 can't be2 (box), must be 3. Hidden single locked.

This cracks it open. Row4 now _,6,3,5,_,1 wait no: col3 row4 empty, but 3 just col1? Row4: col1=3, col2=6, col3 empty, col4=5, col5 empty, col6=1. Needs 2,4. Col3 sees5(r3),2(r5),1(r1 via fills). Push: box2 (rows4-6 cols4-6) has5,1,4(r6c4). So row4 col5=2 (only left for2 in row/box). Row4 col3=4.

Difficult Row: Row 1 – The Final Push

Row1 was stubborn: _ _ 1 _ _ _. After cascades, col1 row1 sees4(r3),3(r4),6? Fills layer: top box forces row1: 3,5,1,6,2,4. Cross-hatch 6's in col4: blocked row2=3,row3=2,row4=5,row6=4, row5 empty but box. Hidden pairs emerge.

Closing Techniques for Speed

• Cross-Hatching: Number X in row Y, slash column possibilities. In 6x6, fewer cells = faster pins. Used on row3 for1,2.
• Hidden Singles: In box/row combo, only one spot for digit. Row4 col1 was pure gold.
• Box Scanning: Per box, place1-6 one-by-one. Top-right gave row1 col6=4 instantly.

From row4 col1=3, grid snowballs: row5 col1=5 (row needs, col open), row5 col2=4, row5 col4=1, row5 col6=6. Row6 col2=3? No: row6 col3=6 (col3 scan), etc. Full grid: row1 3,5,1,6,2,4; row2 6,2,4,3,1,5; row3 4,1,5,2,6,3; row4 2,6,3,5,4,1; row5 5,4,2,1,3,6; row6 1,3,6,4,5,2. Sub-2 min with these. Practice on fullest first, hunt that crucial square. You've got this.