MATLAB: To change value in cells based on conditions

MATLABmatricesmatrix

I have coding as below.
a=[11 11 33 33 22 44; 33 33 33 11 11 22; 33 33 11 22 22 44; 44 44 33 22 44 11]
I need to change the matrix value based on this conditions and cannot overlap each other:
1. if value 33 occured 3 times continuosly, the end of 33 need to replace with 44
33 33 33 = 33 33 44
2. If value 33 appeared 2 times continously and followed by 22, I need to replace the 22 value with 44 too.
33 33 22 = 33 33 44
2. if value 33 occured then followed by value 11, the value 11 will change into 22
33 11 = 33 22
Therefore, origin matrix will become like this:
c=
11 11 33 33 44 44
33 33 44 11 11 22
33 33 44 22 22 44
44 44 33 22 44 11
I need help to code this problem. Thank you for your help.

Best Answer

n = size(a,1);
K = reshape([a zeros(n,1)].',[],1)';
K(strfind(K,[33 33 33])+2) = 44
K(strfind(K,[33 33 22])+2) = 44
K(strfind(K,[33 11])+1) = 22
out = reshape(K,[],n)';
out = out(:,1:end-1);
ADDED [22:16(UTC+4) 05.01.2012]
n = size(a,1);
A = reshape([a zeros(n,1)].',[],1).';
N = numel(A);
j1 = 1;
while j1 <= N
    if j1+2 <= N && (all(A(j1:j1+2) == [33 33 33]) ...
                          || all(A(j1:j1+2) == [33 33 22]) ...
                          || all(A(j1:j1+2) == [33 33 11]))
        A(j1+2) = 44;
        j1 = j1+3;
    elseif j1+1 <= N && all(A(j1:j1+1) == [33 11])
        A(j1+1) = 22;
        j1 = j1+2;
    else
        j1 = j1 + 1;
    end
end
out = reshape(A,[],n)';
out = out(:,1:end-1);
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