How to find repeated array in a matrix

Hello everyone,

Suppose matrix a is like:

a=[1;2;2;3;3;4;5;6;6;7;7;7;8];

and matrix b:

b=[2;7;1;3;2];

Then, I want matrix c to be like:

c = [2;3;10,11,12,1,4,5,2,3]

Matrix c is found an array of matrix b in matrix a, If it finds more than one, then it will write both or more row numbers in the matrix c

Answer 1

[Sara]

d = [];
for i = 1:numel(b)
    d = [d;find(a==b(i))];
end

Answer 2

[Azzi Abdelmalek]

You can use ismember and find function