Problem 54035. Matrix Rotation

Created by Dyuman Joshi

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You are given a 2D matrix of dimension [m,n] and a positive integer r. You have to rotate the matrix r times and print the resultant matrix. Rotation should be performed in alternating layers of matrix 
Example (for r=1)
Start with rotating the outer layer counter-clockwise, reverse the direction with each layer. 
y = [1  2  3  4  5  6           [2  3  4  5  6  12
     7  8  9  10 11 12           1  14 8  9  10 18
     13 14 15 16 17 18      ->   7  20 16 22 11 24
     19 20 21 22 23 24      ->   13 26 15 21 17 30
     25 26 27 28 29 30           19 27 28 29 23 36
     31 32 33 34 35 36]          25 31 32 33 34 35]
y = [7  8  9  10        [8   9 10  11
     6  1  2  11    ->   7   4  1  12
     5  4  3  12    ->   6   3  2  13
     16 15 14 13]        5  16 15  14]
y = ['abcde'        ['bcdej'
     'fghij'    ->   'amghp'
     'lmnop'    ->   'fnoit'
     'pqrst']        'lpqrs']
See test suite for further clarity.

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Last Solution submitted on Jul 18, 2024

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William on 23 Feb 2022

There are several errors in the "correct" values for the tests. For example, text #13 has a capital P replaced with a lower case p. Test 11 seems to have an iincorrect value for n. There are also errors in tests 5, 6 and 8.

Tim on 23 Feb 2022

I'm getting different answers for tests 5, 6, 8, 11, and 13.

Tim on 24 Feb 2022

In test 6 the center point should not change; in test 8 the center 3 by 3 should not change; test 11 would be ok if n=2,6,10,....

William on 24 Feb 2022

I agree with Tim's comments on tests 6 and 8. I would sum things up by saying that the correct results for tests 6, 8, 11 and 12 are:
Problem 6:
y = [2 1 2 1 2; 1 2 1 2 1; 2 1 1 1 2; 1 2 1 2 1; 2 1 2 1 2];
Problem 8:
y = [0 0 0 0 1; 0 1 0 0 0; 0 0 1 0 0; 0 0 0 1 0; 1 0 0 0 0];
Problem 11:
y = [2 1 2 1 2 1 2; 1 4 5 4 3 4 1; 2 3 2 1 2 5 2; 1 4 1 1 1 4 1; 2 5 2 1 2 3 2; 1 4 3 4 5 4 1; 2 1 2 1 2 1 2];
Problem 12:
y = [13 14 15 16; 9 10 11 12; 5 6 7 8; 1 2 3 4];

Tim on 25 Feb 2022

I hate to say it, but tests 8 and 12 still seem to be incorrect.

William on 25 Feb 2022

Yes, I agree. Those two are still comparing to matrices that are different than the correct results that I included in my previous comment.

Dyuman Joshi on 26 Feb 2022

William and Tim, apologies for the fiasco. The test suite has been corrected completely.

Tim, your answer has been rescored and accepted. Do rate the question!

William on 26 Feb 2022

It works! Thanks Dyuman.

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Problem 54035. Matrix Rotation

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