Problem 11. Back and Forth Rows

Solution 208665

Submitted on 26 Feb 2013 by Alfonso Nieto-Castanon

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Shuang-Wei on 6 Jan 2014

brilliant!

niu on 28 Feb 2014

clever!
abs(sort(-cumprod(-ones(n)).*reshape(1:n^2,n,n)',2));
This one is more clear.what do you think?

Test	Status	Code Input and Output
1	Pass	n = 4; a = [ 1 2 3 4; 8 7 6 5; 9 10 11 12; 16 15 14 13]; assert(isequal(a,back_and_forth(n)));
2	Pass	n = 5; a = [ 1 2 3 4 5; 10 9 8 7 6; 11 12 13 14 15; 20 19 18 17 16; 21 22 23 24 25]; assert(isequal(a,back_and_forth(n)));

Test

Status

Code Input and Output

Pass

n = 4; a = [ 1 2 3 4; 8 7 6 5; 9 10 11 12; 16 15 14 13]; assert(isequal(a,back_and_forth(n)));

Pass

n = 5; a = [ 1 2 3 4 5; 10 9 8 7 6; 11 12 13 14 15; 20 19 18 17 16; 21 22 23 24 25]; assert(isequal(a,back_and_forth(n)));