#Three more Sudoku puzzles, courtest of Arvind Ayyer

mm1 := [[0, 5, 4, 0, 0, 0, 2, 7, 0], [9, 7, 0, 0, 0, 0, 0, 8, 0], [2, 0, 
8, 7, 4, 0, 1, 0, 0], [6, 9, 0, 0, 7, 0, 0, 0, 1], [7, 0, 0, 8, 0, 5, 0, 
0, 4], [4, 0, 0, 0, 2, 0, 0, 5, 6], [0, 0, 1, 0, 5, 6, 3, 0, 7], [0, 6, 0, 
0, 0, 0, 0, 4, 2], [0, 4, 7, 0, 0, 0, 6, 1, 0]]
:
mm2 := [[0, 0, 0, 0, 0, 0, 1, 3, 5], [0, 0, 0, 0, 3, 4, 9, 7, 0], [0, 7, 
0, 0, 0, 1, 2, 0, 0], [4, 0, 7, 3, 0, 0, 0, 6, 0], [0, 6, 0, 0, 0, 0, 0, 
5, 0], [0, 9, 0, 0, 0, 7, 4, 0, 3], [0, 0, 1, 5, 0, 0, 0, 8, 0], [0, 5, 9, 
8, 6, 0, 0, 0, 0], [8, 4, 6, 0, 0, 0, 0, 0, 0]]
:

mm4 := [[0, 1, 0, 9, 0, 0, 0, 0, 0], [9, 0, 0, 0, 0, 0, 0, 0, 7], [0, 0, 
2, 0, 0, 7, 4, 0, 1], [0, 0, 8, 0, 5, 0, 0, 0, 0], [0, 9, 0, 8, 4, 6, 0, 
2, 0], [0, 0, 0, 0, 2, 0, 9, 0, 0], [8, 0, 5, 6, 0, 0, 7, 0, 0], [1, 0, 0, 
0, 0, 0, 0, 0, 3], [0, 0, 0, 0, 0, 4, 0, 6, 0]]
: