Puzzler for a Monday

Given a cell array of strings

A = {'MATLAB','HURRAY','SPARKLY','KITTENS','FUN'};

and a particular string value

B = 'KITTENS';

ensure that B is the last element of the cell array. If it isn't, move it to the end of A.

You cannot assume that B appears at all (in which case return A unchanged), but you can assume B does not appear more than once.

[I have a solution, but I post this as a puzzle because I bet someone can find a slicker one.]

Answer 1

[Azzi Abdelmalek]

idx=strcmp(A,B)
out=[A(~idx) A(idx)]

Answer 2

[the cyclist]

Here's mine:

[~,idx] = sort(ismember(A,B));
A = A(idx)

Answer 3

[Sean de Wolski]

idx = ismember(A,B);
C = cat(isrow(A)+1,A(~idx),A(idx))

[Evan]

Awesome. I especially like the "isrow" trick. I'll be remembering that one.

Answer 4

[Evan]

Here's my solution. It's ugly, but I think it's fairly general. :P

function A = cell_shuffle(A)
  idx = cellfun(@(x)isequal(B,x),A);
  A = [A(~idx) A(idx)];
end

This would make for a nice CODY problem, by the way.

Answer 5

[Abdullah Caliskan]

k=ismember(A,B) A(k)='' if sum(k)==0 A=A; else A=[A B] end

Answer 6

[David Young]

[~, idx] = ismember(B, A);
C = circshift(A, [0 -idx]);

[David Young]

Note: does not preserve the ordering of the other elements.