PlaySudoku.us
Hard · Puzzle #209
4
1
3
2
7
2
1
7
5
2
9
1
3
8
3
7
9
4
2
8
9
4
5
7
5
4
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.