How to copy or transfer a portion of matrix to another at same location?

Hi, Is there a way to copy or transfer a portion of matrix A (nonzero values) to another matrix B at same location?

for example:

A = [ 0 0 0 0 0; 0 1 0 1 0; 0 1 0 1 0; 0 0 0 0 0 ];
B = [ 8 8 8 8 8; 8 8 8 8 8; 3 3 3 3 3; 2 2 2 2 2 ];
% desired answer is
C = [ 8 8 8 8 8; 8 1 8 1 8; 3 1 3 1 3; 2 2 2 2 2 ];

Answer 1

[Fangjun Jiang]

index=A~=0;
C=B;
C(index)=A(index);