PlaySudoku.us
Hard · Puzzle #623
9
6
4
3
2
5
2
1
9
1
3
8
3
4
5
7
1
6
3
2
3
4
7
9
5
6
Graph coloring and Sudoku are equivalent problems. Each cell is a node; edges connect cells that share a house. Solving Sudoku = coloring the graph with 9 colors.
Graph coloring and Sudoku are equivalent problems. Each cell is a node; edges connect cells that share a house. Solving Sudoku = coloring the graph with 9 colors.
Graph coloring and Sudoku are equivalent problems. Each cell is a node; edges connect cells that share a house. Solving Sudoku = coloring the graph with 9 colors.
Graph coloring and Sudoku are equivalent problems. Each cell is a node; edges connect cells that share a house. Solving Sudoku = coloring the graph with 9 colors.