by **StrmCkr** » Wed Dec 27, 2006 9:27 am

[Code:]

. . . | . 7 . | 8 6 .

7 1 . | . . 2 | 3 4 .

. 6 8 | . 4 . | . . .

-------+-------+------

6 3 7 | . . . | . . 4

. . 1 | . . . | 6 . .

5 . . | . . . | 7 2 .

-------+-------+------

1 7 . | . 3 . | 4 5 6

. 5 3 | 4 . . | . . 1

. 4 6 | . 1 . | . . .

[/code]

NAKED PAIR (Box): r8c7/r9c7 removes 9 from r8c8

NAKED PAIR (Box): r8c7/r9c7 removes 9 from r9c8

NAKED PAIR (Box): r8c7/r9c7 removes 2 from r9c9

NAKED PAIR (Box): r8c7/r9c7 removes 9 from r9c9

NAKED PAIR (Row): r2c3/r2c9 removes 5/9 from r2c4

NAKED PAIR (Row): r2c3/r2c9 removes 5/9 from r2c5

NAKED PAIR (Col): r8c7/r9c7 removes 2/9 from r3c7

NAKED PAIR (Col): r8c7/r9c7 removes 9 from r4c7

POINTING PAIR: 1s at r3c7/r3c8 points to r3c4, removing 1

POINTING PAIR: 1s at r3c7/r3c8 points to r3c6, removing 1

POINTING PAIR: 2s at r5c1/r5c2 points to r5c4, removing 2

POINTING PAIR: 2s at r5c1/r5c2 points to r5c5, removing 2

POINTING PAIR: 1s at r4c7/r4c8 points to r4c4, removing 1

POINTING PAIR: 1s at r4c7/r4c8 points to r4c6, removing 1

POINTING PAIR: 8s at r8c1/r9c1 points to r5c1, removing 8

NAKED QUAD (Box): r4c4/r4c5/r4c6/r5c5 removes 5/8/9 from r5c4

NAKED QUAD (Box): r4c4/r4c5/r4c6/r5c5 removes 5/8/9 from r5c6

NAKED QUAD (Box): r4c4/r4c5/r4c6/r5c5 removes 8/9 from r6c4

NAKED QUAD (Box): r4c4/r4c5/r4c6/r5c5 removes 8/9 from r6c5

NAKED QUAD (Box): r4c4/r4c5/r4c6/r5c5 removes 8/9 from r6c6

HIDDEN QUAD: 1/3/4/7 in box 5: r6c4 - 1/3/6 -> 1/3

HIDDEN QUAD: 1/3/4/7 in box 5: r6c6 - 1/3/4/6 -> 1/3/4

this solves singles at

r6c5 = 6

r2c5 = 8

and from here the puzzle is all singles.

hope that helps

strmckr

Some do, some teach, the rest look it up.