LinkedIn 6x6 Sudoku #255 Pro-Tips Speed-Run

LinkedIn 6x6 Sudoku #255: Speed-Run Breakdown

Grid hits you with a stacked top-left: 2-1 in row 1, 3 opener in row 2, 4-5 block in row 3. Bottom-right teases with 5-2, 2 empty, 1-5 finish. Classic 6x6 trapdoor setup. Pros don't pencilmark every cell. We cross-hatch surgically, hunt hidden singles, and strike the crucial square to cascade the solve.

Opening Salvo: Cross-Hatch the 6s

Start with cross-hatching on 6. No 6s placed yet, but scan rows 1-3. Row 1 blocks cols 1-2 (2,1). Row 2 blocks col 1 (3). Row 3 blocks cols 1-2 (4,5). In top band boxes, 6 pins to row1 col3. That's your first naked single: row1 col3 = 6.

Drop it. Now row1: [2,1,6,_,_,_]. Cross-hatch 6 again across columns. Col3's 6 slashes row4-6 in box3. Pairs with bottom 5-2-1-5 cluster. Row4 col3 emerges clean for other digits, but hold. Momentum building.

Hidden Single Hunt in Column 6

Sweep col6. Known: row1 empty, row2 empty, row3 empty, row4=2, row5 empty, row6=5. Missing 1,3,4,6. Cross-hatch eliminates: row1 can't take 3 (row2 col1), 4/5 blocked top. Pins hidden single 1 in row2 col6. Bang, row2: [3,_,_,_,_,1].

Chain reaction. Col6 now pressures row3 col6 for 3 or 4 or 6. But row3 has 4-5 early, so scan box2: forces row3 col3=2. Grid cracking.

Difficult Row 5: The Lockpick

Row5 stares back: [_ ,_ ,_ ,_ ,2 ,_]. Col5=2 blocks pairs. Cross-hatch 4 here. Top 4 in row3 col1 eliminates row5 col1. Other 4 spots choked by 1-5-2 in bottom-right. Hidden single: row5 col2=4. Row5 unlocks: [_ ,4 ,_ ,_ ,2 ,_].

This ripples col2. Top 1 and 5 block down, pins row4 col2=6. Boom, mid-band opens.

Crucial Square: Row4 Col1 = 1

Here's the crucial square: row4 col1. After early fills, box1 missing 1,3,6. Cross-hatch 1: top 1 in row1 col2 kills row4 col2. Col1 has 3-4 above, so 1 can't go row5-6 col1 (bottom box pressures). Only row4 col1 survives. Place 1.

Aha! moment. Col1 completes: row4=1 forces row5 col1=5 (only left), row6 col1=6. Bottom row cascades: row6 col2=2 (pairs with col2 1-4-5), col3=4, done. Mid rows chain-fill via naked singles. Full grid drops in 90 seconds.

Pro-Tips for 6x6 Speed

• Band Focus: Top band givens dense? Cross-hatch 6 first, always exposes singles in 2x3 boxes.
• Hidden Singles Trump Pencilmarks: In row5/col6 clusters, scan one digit per house. Eliminate via intersects, not full lists.
• Crucial Square Drill: When stalled, pick emptiest box (box4 here), cross-hatch its missings. One cell lights the fuse.
• Cascade Chase: Fill triggers 3+ placements? Prioritize that digit next. Row4 col1 did exactly that.

Drill #255 daily. Next LinkedIn 6x6, you'll sub-60. Sharpen those eyes.