keep first time a value appear in a colomn and replace following ones

Good evening, Supposing I have the following matrix A= 5*3 =[1 1 1; 1 1 1; 1 0 1 ; 1 0 0; 1 0 0] What i want to do is to keep the first zero of each colomn and to replace following zeros by 1, so that i get a matrix B =5*3= [1 1 1; 1 1 1; 1 0 1 ; 1 1 0; 1 1 1]

Thank you in advance

Answer 1

[Roger Stafford]

   B = (A==0);
   B = A + (B & cumsum(B)>1);

Answer 2

[Jos (10584)]

This will keep the first zero in each row of A and replace every following zero with one:

A(A==0 & cumsum(A==0,2)>1) = 1