MATLAB: Assign values to a matrix without a loop

Question

I want to access to some elements of a matrix.

I have a matrix P :

P = [1     2     3     4     5     6     7     8
     2     1     3     4     5     6     7     8
     3     4     2     1     5     6     7     8
     4     3     5     2     6     1     7     8
     5     4     6     3     7     2     8     1
     6     5     7     4     8     3     9     2
     7     8     6     9     5    10     4    11
     8     7     9    10     6    11     5    12
     9    10     8    11     7    12     6    13
    10     9    11     8    12     7    13     6];

and a matrix A :

A = [5     4
     2     8
     1     5
     4     3
     2     6
     2     3
     1     3
     4     6
     4     6
     5     8];

I want to obtain the A element of P in S, for example

S(1,:) = [5 4]
S(2,:) = [1 8]
S(3,:) = [3 5]
...
S(9,:) = [11 12]    
S(10,:) = [12 6]

I konw how to do it with a for loop, but, is there a way to do it without any loop ?

Answer 1

[m,n] = size(P) ;
I = repmat((1:m)',1,2) ;
idx = sub2ind(size(P),I,A) ;
iwant = P(idx)