Access to matrix elements

I have two matrices, A and B. I want to extract values of matrix A based on indexes of B.

Consider B like a pixel position in an image.

A = magic(4)

A =

    16     2     3    13
     5    11    10     8
     9     7     6    12
     4    14    15     1
B = [2 1; 3 3; 2 4]     

This means that I want to have a matrix C like below.

C = [2     6    14]

I've done it with for loop:

for i=1:length(B)
    C(i) =  A(B(i,2),B(i,1));
end

but I'd rather avoid a for loop. How can I do that?

Answer 1

[Matt J]

A = magic(4)

A = 4×4

16 2 3 13 5 11 10 8 9 7 6 12 4 14 15 1

B = [2 1; 3 3; 2 4]     ;

C=A(    sub2ind(size(A),  B(:,2), B(:,1)  )  ).'

C = 1×3

2 6 14