PlaySudoku.us
Medium · Puzzle #550
2
9
7
8
1
5
3
7
4
2
1
2
5
6
4
5
9
5
7
8
7
6
8
4
3
2
2
4
4
7
6
9
1
1
4
9
3
The brain releases dopamine when it solves a puzzle — the same reward chemical triggered by food and exercise.
The brain releases dopamine when it solves a puzzle — the same reward chemical triggered by food and exercise.
Retired architect Howard Garns, who invented the modern Sudoku, never knew it became a global phenomenon — he died in 1989.
Retired architect Howard Garns, who invented the modern Sudoku, never knew it became a global phenomenon — he died in 1989.