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Problem B
Magical Mystery Knight's Tour

A knight’s tour on a rectangular board of $n$ rows and $m$ columns of squares (traditionally $8$-by-$8$) is a labelling of the squares by integers $1$ through $n \cdot m$ so that label $n+1$ is a knight’s move from label $n$. That is, $2$ squares horizontally and $1$ square vertically or $1$ square horizontally and $2$ squares vertically. The image below shows an $8$-by-$8$ knight’s tour.

\includegraphics[width=.35\textwidth ]{knight-001.png}

A knight’s tour (on a square board) is (semi-)magical if the sum of the values in each row and column is the same (for the $8$-by-$8$ case the sum would be $260$). For this problem, you will be given a sequence of semi-magical $8$-by-$8$ knight’s tours with many of the labels removed (see the image below). Write a program to fill in the missing labels so the knight’s tour is semi-magical.

\includegraphics[width=.35\textwidth ]{knight-002.png}

Input

The input contains a single data set consisting of $8$ lines of input. Each line contains $8$ integers separated by spaces giving the labels for the corresponding row. If the label value is $-1$, the label has been removed and your program is to find the correct value to put in that place. There will be at most $45$ removed labels with the value $-1$. You may assume that the starting point of the tour (labeled $1$) was not removed and thus appears in the input.

Output

Output $8$ lines containing $8$ integers each, separated by spaces, filling in the removed values to give a complete semi-magical knight’s tour which includes the positive labels from the input. There may be multiple correct answers. Your result will be graded correct if it is a semi-magical knight’s tour and the positive labels from the input are in the same square in your answer.

Note: Your output does not have to be lined up as shown in the Sample Output. Just make sure that each of the $8$ lines of output has at least one space between each value on the line.

Sample Input 1 Sample Output 1
1 48 -1 -1 33 -1 63 18
30 51 -1 3 -1 -1 -1 -1
-1 -1 -1 -1 15 -1 -1 -1
-1 -1 -1 45 -1 -1 36 -1
-1 -1 25 -1 9 -1 21 60
-1 -1 -1 -1 24 57 12 -1
-1 6 -1 -1 39 -1 -1 -1
54 -1 42 -1 -1 -1 -1 -1
 1 48 31 50 33 16 63 18
30 51 46  3 62 19 14 35
47  2 49 32 15 34 17 64
52 29  4 45 20 61 36 13
 5 44 25 56  9 40 21 60
28 53  8 41 24 57 12 37
43  6 55 26 39 10 59 22
54 27 42  7 58 23 38 11

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