How to find position of value in matrix and write as another matrix

Lets say i have this matrix

A = [1 0;
     0 0;
     1 1;
     0 1;
     0 0]

Now i want to write the positions of line of value "1" in another matrix B. In A it should start from column1. answer should be like this

B=[1 3 3 4]

which is in column1 value"1" is at 1 and 3, and in column 2 value"1" is at line 3 and 4.

Answer 1

[the cyclist]

[ii jj] = find(A);
B = ii';

Since you don't need the jj index, you can just do

[ii ~] = find(A);
B = ii';

instead.

[Akmyrat]

thanks a lot cyclist...Same A matrix with one more column A=[1 0 0;0 0 1;1 1 0;0 1 0;0 0 0]. i want result to be like that B=[1 3 2 3 4], which is from top to down 1 and 3 position in !st column, 2 position in 3rd column, 3 and 4 position in 2nd column. can u help please.

Answer 2

[Andrei Bobrov]

on Akmyrat's comment

[B,~] = find(A(:,[1 3 2]));
B = B';

[Akmyrat]

thanks a lot Andrei...:)