Make a vector of 1's and zeros

I could like to make a matrix consisting of 1's and zeros at certain points. I have a vector that is made up of two other vectors; C = [ A A1] and B = sort[C]

I wish to make a vector that is one at the points A and zero at A1. Because these are interspersed I am confused on how to do this. I tried using find but because A has a different length to C I cant use it for this purpose. Any ideas would be great :)

Answer 1

[Azzi Abdelmalek]

A=[1 2 3 4]
B=[2 6 1 5]
[C,idx]=sort([ A B])
C(idx<=numel(A))=1;
C(idx>numel(A))=0

[Bran]

Thank you very much for the help!