question: public int computeArea ( int A , int B , int C , int D , int E , int F , int G , int H ) { int areaA = ( C - A ) * ( D - B ) ; int areaB = ( G - E ) * ( H - F ) ; int left = Math . max ( A , E ) ; int right = Math . min ( C , G ) ; int bottom = Math . max ( B , F ) ; int top = Math . min ( D , H ) ; int overlap = 0 ; if ( right > left && top > bottom ) { overlap = ( right - left ) * ( top - bottom ) ; } return areaA + areaB - overlap ; }
target:  The total area covered by two rectilinear rectangles is the sum of the two rectangles subtracted by their overlapping area.