simple_script

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

=square1 {
    0,0:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square2 {
    0,3:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square3 {
    0,6:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square4 {
    3,0:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square5 {
    3,3:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square6 {
    3,6:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square7 {
    6,0:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square8 {
    6,3:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}

=square9 {
    6,6:
    +1.+0,
    +2.+0,
    +0.+1,
    +1.+1,
    +2.+1,
    +0.+2,
    +1.+2,
    +2.+2,
}



=rows {
    +1.+0,
    +2.+0,
    +3.+0,
    +4.+0,
    +5.+0,
    +6.+0,
    +7.+0,
    +8.+0,
}

=cols {
    +0.+1,
    +0.+2,
    +0.+3,
    +0.+4,
    +0.+5,
    +0.+6,
    +0.+7,
    +0.+8,
}

=knights {
    +2.+1,
    +1.+2,
    -1.+2,
    -2.+1,
    -2.-1,
    -1.-2,
    +1.-2,
    +2.-1,
}

=cells {
}

+assert(1 <= cells)
+assert(cells <= 9)

+distinct(rows)
+distinct(cols)
+distinct(square1)
+distinct(square2)
+distinct(square3)
+distinct(square4)
+distinct(square5)
+distinct(square6)
+distinct(square7)
+distinct(square8)
+distinct(square9)

solve