Replace elements in binary matrix

I have a binary image and want to replace all the zeroes with 1s and all the 1s with zeroes. ( so that the binary image is totally opposite to original image). How can i do that?

Answer 1

[Michal]

% B original binary matrix
% B_ new binary matrix 

B_ = ~B;

[Abdul Salam]

Thanks

Answer 2

[Walter Roberson]

B_ = imcomplement(B);