Doubt at timestamp 11:00

#1

shouldn’t it be n-i+1 and m-j+1?

#2

last cell index is n-1,m-1
so no of element form (i,j) to ( n-1.m-1) will be length *breadth of rectangle formed

length=(n-1-i+1)=(n-i)
breadth=(m-1-j+1)=(m-j)

so it should be (n-i)(m-j)

i hope this help
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