User input for hierarchical and grid ALV...

Hello Experts, 

I have developed a report wherein users can choose to display it in hierarchical grid ALV.
Both formats have a column that lets users enter numeric values. My question is, how do I 
reflect the values they entered in other column and the subtotal? for example, user A entered 1,000,000 in 
column C. Now I want it to reflect or in other words add 1,000,000 to column D. Below is a 
'graphical' explanation:

BEFORE user enters 1,000,000 in column C:

		A		B		C		D
		100		50				1,000,100
SUBTOTAL: 	100		50		0		1,000,000

AFTER user enters 1,000,000 in column C:

		A		B		C		D
		100		50		1,000,000	1,000,150
SUBTOTAL: 	100		50		1,000,000	1,000,000

NOTE that column D relects the changes in column C and also the subtotal. This is for both 
hierarchical and grid ALV. The FM's I used are REUSE_ALV_HIERSEQ_LIST_DISPLAY for hierarchical
and REUSE_ALV_GRID_DISPLAY for grid. Hope you can help me guys. Thank you and take care!