Consider the dependence equations:
 
  for   
S:   A[  
 for  
There are two potential dependences arising from the three references to A.
 = 0 to 3 do
  = 0 to 3 do
 = 0 to 3 do
  = 0 to 3 do
 ,
 ,  ] := A[
 ] := A[  ,
 ,  ] + A[
 ] + A[  ,
 ,  ]
 ]
Therefore two systems of dependence equations to solve:
((strictly we should also consider output dependences between A[ ,
 ,  ] and A[
 ] and A[  ,
 ,  ], but this is
obviously absent)).
 ], but this is
obviously absent)).