PlaySudoku.us
Hard · Puzzle #821
9
1
5
3
7
3
6
9
7
4
5
9
2
3
9
3
6
9
6
1
2
5
1
8
3
7
8
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.