Week 4: Wednesday
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Q1. (40)

Input a 3x3 matrix, and output all 2x2 square matrices in it. The rows and
columns of the 2x2 matrices must be adjacent in the original matrix. For each
such matrix, also output the sum of its elements.

Q2. (60)

Input a matrix of size 3x3. For each column and row, find the sum of the
elements in it. Output the matrix such that both the columns and rows are
re-arranged in the increasing order of their sums. If two columns or two rows
have the same sum, output them in the order they appeared in the original
matrix.

Example:
If input is
1 4 8
9 2 9
8 6 0
then output should be
4 8 1
6 0 8
2 9 9