LinkedIn 6x6 Sudoku #431 Speed-Run Guide

Pro-Tips for LinkedIn 6x6 Sudoku #431

This is a tidy speed-run board: the clues look sparse, but the 2-by-3 boxes give you enough leverage to avoid guessing. Track digits 1 through 6, and let intersections do the work.

Start with Cross-Hatching

Scan each box, then project its missing digits across the matching rows and columns. The upper-left box already contains 1, so its remaining candidates are restricted sharply by the 2 and 3 clues nearby. Do the same in the upper-middle box, where 2, 3, and 4 compress the open lanes.

The key habit is to avoid solving one row in isolation. Every placement should immediately be checked against its box and column. In a 6x6 grid, that three-way check is fast and usually stronger than ordinary row scanning.

The Crucial Square

The breakthrough comes in the middle-right box. Its visible 2 and 3, combined with the 4 already fixed below, leave only a narrow home for 6. Once that square is secured, the rest of the box resolves by elimination.

That placement also attacks the difficult fourth row. With 2 and 1 already present, the row's missing digits become a compact candidate set. The column restrictions then force 5, followed by 4 and 6. This is the puzzle's main Aha! moment: a box deduction unlocks a row, and the row feeds the next box.

Use Hidden Singles, Not Hunches

After the central chain opens, look for digits that have only one legal location within a row or box. In the lower-left region, the existing 2 and 4 clues eliminate several lanes, making a hidden single for 6 appear. Place it confidently, then rescan the lower rows.

The bottom band is especially cooperative. The fixed 3 and 4 clues constrain their columns, while the lower-right box limits the remaining positions. Do not fill cells merely because they have two candidates. Wait for the hidden single or the box intersection that removes the ambiguity.

Finish the Chain

Once the difficult row is complete, the upper-right section collapses quickly. Its remaining values are determined by the columns rather than by brute force. Continue alternating between:

• Box scan: find the only legal location for a digit.
• Column sweep: remove that digit from intersecting rows.
• Row check: confirm whether the new restriction creates a hidden single.

The completed grid is:

4 1 5 6 2 3
2 6 3 4 5 1
6 3 2 5 1 4
5 4 1 2 3 6
1 5 4 3 6 2
3 2 6 1 4 5

Every row, column, and 2-by-3 box contains 1 through 6 exactly once. The clean solve for #431 is to prioritize the middle-right box, exploit the difficult fourth row, and let each forced placement generate the next one.