@12:40 in this algo there is need to traverse coloumn wise for all submatrix… i mean yes after forming top left bottom right we know submatrix but just adding them wont give sum of all submatrix?
like here traverse for first loop:
li=0,lj=0
bi=1,bj=1
3rd loop only traverse :
00 to 01
10 to 11
here row wise traverse occur but what about submatrix:00 to 10 and 01 to 11?
as simply here sum variable is adding individual elements in row wise
Traverse coloumn wise
@himanshu0ayush There are 6 loops in the solution. The first two take the top left point, then 3rd and 4th loop takes the bottom right point.
Finally loop 5 and 6 are responsible for adding all elements present inside each cell in all the rows and columns.
So basically they are including all the cells between top left and bottom right.
@amankumarkeshu never mind got it in the video he was explaning for all possible submatrix but while explaining code he said all rectangular submatrix
Okay great. Good luck.