Nov 19 - Very Hard
Puzzle Copyright © Kevin Stone
Share link – www.brainbashers.com
Reasoning
R4C5 can only be <2>
R6C9 can only be <2>
R9C4 can only be <5>
R9C6 can only be <4>
R6C5 can only be <4>
R5C6 can only be <3>
R5C5 can only be <9>
R1C6 can only be <2>
R6C1 can only be <1>
R1C4 can only be <9>
R7C5 can only be <1>
R5C4 can only be <8>
R9C5 can only be <7>
R5C7 is the only square in row 5 that can be <1>
R9C7 can only be <2>
R2C8 is the only square in row 2 that can be <2>
R5C1 is the only square in row 5 that can be <2>
R7C2 is the only square in row 7 that can be <2>
Squares R4C9 and R5C9 in column 9 form a simple naked pair. These 2 squares both contain the 2 possibilities <56>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.
R2C9 - removing <5> from <357> leaving <37>
R3C9 - removing <56> from <34568> leaving <348>
R7C9 - removing <5> from <458> leaving <48>
R8C9 - removing <5> from <3457> leaving <347>
Squares R3C1 and R3C9 in row 3 and R7C1 and R7C9 in row 7 form a Simple X-Wing pattern on possibility <4>. All other instances of this possibility in columns 1 and 9 can be removed.
R8C1 - removing <4> from <459> leaving <59>
R8C9 - removing <4> from <347> leaving <37>
Squares R2C1 and R8C1 in column 1 form a simple naked pair. These 2 squares both contain the 2 possibilities <59>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.
R3C1 - removing <5> from <4568> leaving <468>
R4C1 - removing <5> from <56> leaving <6>
R7C1 - removing <5> from <458> leaving <48>
R4C9 can only be <5>
R5C3 can only be <5>
R5C9 can only be <6>
R7C8 is the only square in row 7 that can be <5>
Squares R2C9 and R8C9 in column 9 form a simple naked pair. These 2 squares both contain the 2 possibilities <37>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.
R3C9 - removing <3> from <348> leaving <48>
Squares R3C1 and R3C9 in row 3 form a simple naked pair. These 2 squares both contain the 2 possibilities <48>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the row.
R3C2 - removing <8> from <568> leaving <56>
R3C8 - removing <8> from <368> leaving <36>
Squares R7C1<48>, R8C3<14>, R9C2<168> and R9C3<16> in block 7 form a comprehensive naked quad. These 4 squares can only contain the 4 possibilities <1468>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the block.
R8C2 - removing <1> from <159> leaving <59>
Squares R8C1, R8C2, R2C1 and R2C2 form a Type-1 Unique Rectangle on <59>.
R2C2 - removing <59> from <159> leaving <1>
R2C3 can only be <3>
R2C9 can only be <7>
R2C7 can only be <5>
R8C9 can only be <3>
R8C8 can only be <1>
R2C1 can only be <9>
R1C7 can only be <4>
R8C3 can only be <4>
R9C8 can only be <8>
R9C2 can only be <6>
R7C9 can only be <4>
R1C3 can only be <6>
R8C7 can only be <7>
R3C9 can only be <8>
R8C1 can only be <5>
R3C1 can only be <4>
R7C1 can only be <8>
R8C2 can only be <9>
R9C3 can only be <1>
R3C2 can only be <5>
R1C8 can only be <3>
R1C5 can only be <5>
R3C8 can only be <6>
R3C5 can only be <3>
R1C2 can only be <8>
Today's Sudoku Puzzles
All daily items change at midnight GMT – set your local time zone.
Note: BrainBashers has a Dark Mode setting.