vhdl code

hi, i want a vhdl code for following logic.
i have 20 signed numbers,like.
-2 -2 0 0 0 0 -2 -2 0 0 0 0 2 2 0 0 0 0 2 2
1) i want to put them in group of 4 numbers like,
-2-200 00-2-2 0000 2200 0022
2)i want sum of that all each group internally like
-2+-2+0+0 = -4
0+0+-2+-2= -4
0+0+0+0=0
2+2+0+0=4
0+0+2+2=4
3) i want put this answers in seperate memory
like,
-4 -4 0 4 4
last i want this signed vector in memory.

can anyone help me?

thank u.

regards,
AAP😛